Case Interview: all you need to know (and how to prepare) | MyConsultingCoach

Case Interview: A comprehensive guide

What is a case interview?

Case interviews are the core of the selection process right across McKinsey, Bain, BCG, the consulting wings of the Big Four and any other high-end consultancies. To land a job at any of these firms, you will have to ace multiple case interviews. Before we can figure out how to prepare for a case interview, we will first have to understand in detail what you are up against. What format does a consulting case interview take, what is expected of you and how will you be assesed? Let's dive right in and find out!

Case interview format

Case interviews take very similar formats across the various consultancies where they are used. Before landing an offer at McKinsey, Bain, BCG or any similar firm, you will have to complete between four and six case interviews, divided into two rounds, with each interview lasting approximately 50-60 minutes. Here is the typical case interview timeline:

  1. First 15-30 minutes: Fit Interview, assessing your motivation to be a consultant in that specific firm and your leadership and teamwork traits. Learn more about the fit interview in our article here.

  2. Next 30-40 minutes: Case Interview

  3. Last 5 minutes: Fit Interview, again. This time it’s about your questions for the interviewer.

Both the Case and Fit interviews play crucial roles in the finial hiring decision. There is no “average” taken between case and fit interviews: if your performance is not up to scratch in either of the two you will not be able to move on to the next interview round or get an offer.

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Difference between first and second round interviews

Despite interviews in the first and second round following the same format, seniority of the interviewer, time pressure (with usually three interviews in a row) and value at stake make a second round consulting case interview potentially one of the most challenging moments of your working life. There are three key differences between the two rounds:

  1. Time pressure: the Final Round case interviews test your ability to perform under pressure, with three interviews in a row and often very small breaks between them

  2. Focus: Since interviewers in the Second Round tend to be more senior (usually partners with 12+ years experience), they will be more interested in your personality and ability to handle challenges independently. Some partners will drill down into your experiences and achievements to the extreme. They want to understand how you react to challenges and your ability to identify and learn from past mistakes.

  3. Psychological pressure: while case interviews in the first round are usually more focused on having you simply crack the case, second round interviewers often use the "bad cop" strategy to test the way candidates react to challenges and uncertainty.

Frame the Airline Case Study

Is there a difference between McKinsey and other firms?

McKinsey case interviews are not overwhelmingly different to those given by Bain, BCG and other firms, with the McKinsey interview timeline breaking broadly the same as the one set out above. However, there are some differences in the specifics of how McKinsey administer both their case and fit interviews which is will pay to be aware of if you are applying to that firm.

McKinsey Case Interviews Most consulitng case interview questions test your ability to crack a broad problem, with a case prompt often going like: "How much would you pay for a banking licence in Ireland?". You, as a candidate, are expected to identify your path to solve it (structure), leveraging your interviewer to collect the data and test your assumptions.

However, a McKinsey case interview - especially in the first round - is slightly different, with the interviewer controlling the pace of the conversation much more than in another case interviews. At McKinsey your interviewer will ask you a set of pre-determined questions, regardless of what your initial structure is. For each question, you will have to understand the problem, come up with a mini structure, ask for additional data (if necessary) and come to the conclusion that answers the question.

Essentially, interviewer-led case studies are large cases made up of lots of mini-cases. The method you have to follow is basically the same as in the standard (or candidate-led) cases; with the main difference simply being that, instead of solving one big case, you are solving several mini cases sequentially.

McKinsey Fit Interview - the McKinsey PEI
As with their cases, McKiney take a slightly more structured approach to the fit component of their interviews than do other firms. Indeed, the fit component of a McKinsey interview is sufficiently formalised that it has its own name - the McKinsey Personal Experience Interview, or McKinsey PEI for short.

There are two to three rounds of PEI and is typically more intense than the fit interviews of other firms, with each interview focusing on only one topic, but drilling down to an extreme.

As with case studies, the McKinsey format is slightly different - and it is good to know this in advance - but this doesn't actually affect your prep. You should be fully prepped and ready for an intense fit interview from Bain or BCG as well! See our section on the fit interview below and our article here to get started.

The McKinsey PST and Other Differences
It is also worth noting here that McKinsey will require you to pass a written problem solving test - The McKinsey PST - before you will be invited to interview at all. This is broadly similar to the tests administered by Bain and BCG, but has its own unique format and other details which you will need to be aware of.

Since the general pass rate for this test is only 33%, it is something you are going to have to take seriously and prepare for thoroughly. Start with our free comprehensive McKinsey PST Guide.

If you are curious, you can read more about the differences between McKinsey, Bain and BCG in our blog post on that subject.

Case interview topics

Several self-proclaimed consulting gurus have made fortunes out of creating notionally comprehensive lists of a dozen or so case types and then selling a ready-made recipes for each - apparently able to solve all instance of each case type. All business problems can be reduced to one of these case types and each type of case can be solved by using generic frameworks. If you believe the hype, Case in Point or Case Interview Secrets hold within their pages the solutions to all of the world’s business conundrums!

Straight off the bat, this should strike you as suspect. If all business issues really could be reduced to a finite number of case types, with sufficiently regular structures that we really could apply the same simple frameworks, then why would anyone pay to hire management consultants? Would they not just pick up a copy of one of these books from Amazon and save themselves tens of thousands?

The truth is both simpler and more complex. Cases are profoundly more varied than these frameworks can hope to take account of. However, we can still group cases into a set of recurring, common topics which they tend to be built around.

These topics are not as distinct as those promoting frameworks might have it. Topics will often overlap and we can expect to see more than one in the same case question. For example, taking a handful of the categories below, it is perfectly reasonable to suppose that a pricing decision could impact a company’s competitive position in the market, which could then impact profits and thus the firm’s valuation.

We give a brief run through of each topic below — including example case interview questions for each. We will also return to the same ideas in our section on “Building Blocks”.

Estimates

Estimation is a central theme in both day-to-day consulting work and in case interview questions. When we estimate, we make educated guesses to establish values in the face of incomplete data. Consulting estimations will combine such a guessed factor with a quantitative factor to come up with reasonable estimates of unknown facts.

It is important to note that, when an interviewer asks you to make an estimation, it is not because they particularly care what the correct answer is (they could find out without asking you), but rather that they want to assess that you can move towards an answer in a structured, rational manner. The watchword in your approach to all estimations should be to be “reasonable”. Even if answers end up being factually incorrect, what is important is that they can be supported by a compelling rationale.

Examples

  • How many bank branches are there in Italy?
  • How many cars are sold in Berlin in one year?
  • How many people will buy the latest high-tech smartphone on the market?

Remember that, for all these different flavours of case study, we have plenty of example case questions for you to work through in our free Case Bank.

Profitability

The fundamental goal of any normal business is to maximise profits — nobody is getting up and going to work with the object of losing money. As such, business problems around profitability are bread and butter issues for management consultants.

Clients will very often tell broadly the same story. The business was doing in well in recent years, with strong profits. However, some recent turn of events has upset this state of affairs and led to concerns around profit levels. Consultants are thus engaged, as businesses are often sufficiently complex that it can be difficult to figure out precisely where and why the company is losing money - let alone how to then reverse the situation and restore healthy profits.

Example

Despite steady growth in customer flow, the Walfort supermarket chain has seen falling profits in the past year. What is the reason for this decline?

Pricing

For a company to be profitable at all, it is a pre-requisite that it charges the correct price for whichever products it sells. However, establishing what price to charge for any one product — or indeed a whole suite of related products — can be a highly complex business. Consultants are often engaged to negotiate the many salient variables, with their complex interdependencies, which need to be accounted for in pricing. Correspondingly, then, pricing questions are a also common theme in case interviews.

Examples

  • A company launches a new smartphone with a significantly improved camera. How much should they charge?
  • A doughnut chain wants to start selling coffee in their shops. How much should they charge per cup?

Valuation

Valuation will be essential to underpinning any investment decision. In short, if we want to know how much we should be willing to pay to acquire a company or asset, we need to understand how much it is worth to us. Thus, you can expect valuation to be at the heart of case questions on mergers and acquisitions.

Examples

  • Our client is a steel producer who wants to expand by acquiring their competitor. The competitor offers to sell their plant for $1m. Should our client accept this deal?
  • How much should a restaurant chain bid in an auction for the rights to run a restaurant in the British Museum for one year?

Competitive Interaction

Of course, profit levels, the values of companies and the prices of products can all change with time. Generally, these will fluctuate because of changes in the competitive landscape of the relevant market. Thus, Nokia and Kodak dominated the mobile telephone and photography markets until new companies with new products dramatically shook things up. In such circumstances, company profits and valuations slide rapidly and prices are often slashed in attempts to maintain sales.

New market entrants or old competitors with new ideas can throw a company’s whole business model up in the air overnight, with consultants often called in to advise on the potentially major changes which might be required to survive (and ideally prosper).

Example

You are running an airline and a low cost competitor like Ryanair decides to start operating on your routes. You are rapidly losing customers to their lower fares. How do you respond?

Skills required in a consulting interview?

In Cases there is no right or wrong answer, what really matters is the way you think the problem through, how confident you are with your conclusions and how quick you are with back of the envelope arithmetic. If you visit McKinsey, Bain and BCG website pages on case interview, you will find that the three firms look for very similar traits. Broadly speaking, your interviewer will be evaluating you across 5 areas:

One: Probing mind

Showing intellectual curiosity by asking relevant and insightful questions that show critical thinking and a proactive nature. For instance, if we are told that revenues for a leading supermarket chain have been declining over the last 10 years, a successful candidate would ask:

We know revenues have declined. This could be due to price or volume. Do we know how they changed over the same period?

instead of a laundry list of questions such as:

  • Did customers change their preferences?

  • Which segment has shown the decline in volume?

  • Is there a price war in the industry?

Two: Structure

Structuring means creating a framework, i.e. a series of clear consecutive steps in order to get to a solution to the problem. The focus of case interview frameworks (and of the whole case in general) is not on reaching solution themselves, but rather on how to get there.

This is the trickiest part of the case interview and the main reason for candidates failing their case interviews. Millions were made by selling books such as Case in Point describing 10 or 12 standardised frameworks, which were said to be the passkey to solve virtually any case on earth. As we noted above, if we believed all the claims made of these frameworks a simple case interview frameworks cheat sheet might solve all the world's business problems and/or land you a job in McKinsey every time.

Unfortunately, this approach to case interviews simply does not work in practice, for a few reasons. First Consultants are not naïve enough to hire people who are just good at memorizing 12 schemes. Second because you are expected to think exactly in the same way a real consultant would do in a real case. Since no consultant uses pre-packaged frameworks in real projects (feel free to ask all your friends in consulting), do you think they expect you to use them in an interview which is set to represent as closely as possible their work?

This is why we created the Problem-driven Structure. As ex-consultants, we aim to teach candidates what real consultants do in real projects. That is, crafting a tailored framework for every case. The key pieces of your structure should be:

  • Proper understanding of the objective of the case. Ask yourself: "What is the single crucial piece of advice that the client absolutely needs?"

  • Identification of the drivers: Ask yourself: "What are the key forces that play a role in defining the outcome?"

At first sight this case cracking concept looks pretty intuitive. However this is a radically different approach from the typical one-size-fits-all method of trying to force-fit one or more generic frameworks (such as the Case in Point frameworks) to a case. Let’s understand why with a simple case question.

Our client is PharmaCorp, a Dutch pharma company specialized in researching, developing, and selling “small molecule” drugs. This class of drugs represents the vast majority of drugs today, including aspirin and blood-pressure medications. PharmaCorp is interested in entering a new, growing segment of drugs called “bionics”. These are complex molecules that can treat conditions not addressable by traditional drugs. R&D for Bionics is vastly different from small molecule R&D. PharmaCorp wants to jumpstart its biologicals program by acquiring BioHealth, a leading bionics startup from the Silicon Valley with a promising drug pipeline. Should PharmaCorp acquire BioHealth?

Check out the difference between the standard framework-based approach and our Problem-driven Structure.

Three: Problem solving

You’ll be tested on your ability in identifying problems and drivers, isolating causes and effects, demonstrating creativity and prioritising issues. In particular, the interviewer will look for the following skills:

  • Prioritising: Can you tell a relevant from an irrelevant fact?

  • Connecting the dots: Can you connect new facts and evidence to the big picture?

  • Establishing conclusions: Can you establish the right conclusions without rushing to conclude facts not supported by evidence?

Four: Numerical agility

In case interviews, you are expected to be quick and confident with (precise and approximated) numbers. This translates into:

  • Performing simple calculations quickly: essential to solve cases quickly and impress clients with quick estimates and preliminary conclusions.

  • Analysing data: extract data from graphs and charts, elaborate it and draw insightful conclusions.

  • Solving business problems: translate a real world case to a math problem and solve it.

Our article on consulting math is a great resource here, though the math lecture and other math content in our MCC Academy is the best and most comprehensive material available.

Five: Communication

As in real consulting work, coming up with the best ideas in a consulting case interview is necessary, but not enough: you must be able to turn your answer into a compelling recommendation. Otherwise your days and nights of hard work spent on case interview prep have been totally wasted.

So, how do you make sure that your recommendations come across as relevant, smart and engaging? By mastering CEO-level communication. It sounds easier than it is, since speaking like a CEO often entails presenting your case interview answers by doing exactly the opposite of what you would do when telling a story to your mum. Here are three key areas to focus on in your communications:

  • Top down: A CEO wants to hear the key message first, and then - if and only if they find it useful - they'll ask you to provide details. Always think about what is absolutely critical for the CEO to know, and start with that. You can read more on our section about the Pyramid Principle.

  • Concise: This is not the best time for boiling the ocean or going through an endless number of possible solutions. Consultants want a structured, quick and concise recommendation for their business problem they can implement the next day.

  • Fact-based: Consultants share CEOs' hatred of opinions based on gut feel rather than facts. They want facts first, to make sure you are in control. Always back up your conclusions with the relevant facts.

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How to crack any case interview like a McKinsey, BCG or Bain consultant would

The MyConsultingCoach team, a group of seasoned McKinsey, Bain and BCG consultants with experience on both sides of the interview table, has developed a new, proprietary approach to case cracking which replicates how top management consultants approach actual engagements.

The key is decoupling problem solving, business concepts and analysis tools to achieve the necessary modularity to apply the same overarching method to solve any case. The synergic action of these three elements will allow you to tackle any case interview question. Let's look at these elements in more detail.

The problem driven structure

MyConsultingCoach’s Problem Driven Approach is a universal problem solving method that can be applied to any business problem irrespectively of its nature. It works by generating a bespoke framework for each individual case question and is a simplified version of the roadmap McKinsey consultants use when working on engagements. The canonical seven steps from McKinsey are simplified to four as the analysis required for a six month engagement is clearly different from that of a 45 minute case study. However, the underlying flow is the same. Let's take a look.

Identify the problem

Many candidates will manage to irretrievably mess up their cases within the first few minutes of starting off. Often, these candidates will not realise what they have done until they are getting near the end of their analysis. It is then that they suddenly see that they have misunderstood the case prompt — and have effectively been answering the wrong question all along! With no time to go back and start again, there is nothing to do. Even if there were time, making such a silly mistake so early on will also make a terrible impression on your interviewer, who might well have written them off already. The interview is scuppered and all their preparation has been for nothing.

This error is so disappointing as it is so readily avoidable. In this context, it is an inherent advantage that our case method places huge importance on laying the foundations for analysis by ensuring a full understanding of the case prompt. Once we have identified the fundamental, underlying prob lem our client is facing, we focus our whole analysis around finding solutions to this specific issue.

Now, some prompts are easy to digest. For example, “Our client, a supermarket, has seen a decline in profits. How can we bring them up?” However, many of the prompts given in management consulting case interviews are much more difficult and might come from unfamiliar business areas or industries. For example, “How much would you pay for a banking license in Ghana?” or “What would be your key areas of concern when setting up an NGO?”

Don’t worry if you have no idea how you might go about tackling some of these prompts! In the lesson on identifying the problem in our MCC Academy course, we teach you how use a structured, hypothesis-driven approach to quickly circumscribe the key issue facing the client. We provide you with a systematic, four step approach to identifying the problem as well as running through common errors to ensure that you start off on the right foot every time!

Four Steps to Identify the Problem

As a final point, it goes without saying that showing this level of diligence early on where so many other candidates do not is a great start in terms of impressing your interviewer!

Frame a solution

After you have fully understood the problem, it is time to move to draw up a bespoke structure to capture all the unique features of the case and to guide your analysis . This is precisely the same method used by real consultants working on real engagements.

Of course, it might be easier to simply roll out one old-fashioned framework or another — it is true that it would be faster (at least at this stage) and require less thought than the problem driven structure approach. We are honest that our approach requires more work from you. However, our method comes with the crucial advantage being able to accommodate the most difficult and irregular of cases (exactly the kind you can expect at an MBB interview). Since we start from first principles every time, we can tackle any case with just the same overarching method . As we note in the relevant section here, is a huge advantage over frameworks, which cannot be relied upon to work in any case which departs from their very rigid schemes .

In practice, structuring a problem in line with our method will generally mean drawing up a tree structure - either an issue tree or an hypothesis tree, depending on how you are trying to address the problem. These trees break down the problem into a set of smaller problems, which you can solve individually. Representing this on a diagram makes it easy for both you and your interviewer to keep track of your analysis.

To see how this is done, let’s look at an issue tree breaking down the revenues of an airline. These can be segmented as number of customers multiplied by average ticket price. The number of customers can be further broken down into number of flights times number of seats times average occupancy rate. The node corresponding to average ticket price can then be segmented further.

Frame the Airline Case Study

A good structure meets several requirements, including MECE-ness, level consistency, materiality, simplicity and actionability. It is worth noting, though, that the same problem can be structured in multiple valid ways by choosing different means to segment the key issues. It is important to master segmentation so that you can chose a scheme which is not just valid, but actually useful in addressing the problem.

After taking the effort to identify the problem properly, an advantage of the problem driven structure is that it will help ensure that you stay focused on that same fundamental problem throughout. This might not sound like much, but a large number of candidates get lost in their own analysis and end up taking huge tangents, ending up with an answer to a question they weren’t asked.

One issue which occurs quite often — and tends to be an issue with certain frameworks — is that the candidates come to the end of their analysis and, even if they have stuck to the initial question, have not actually reached a definite solution; perhaps generating a laundry list of pros and cons with no single recommendation for action. Clients employ consultants for actionable answers and this is what is expected in case interview. The problem driven structure excels in ensuring that everything you do is clearly related back to key question in a way that will generate a definitive answer. Thus, the problem driven structure builds in the hypothesis driven approach so characteristic of consulting practice.

You can learn how to set out your own problem driven structures in our article here and in our MCC Academy course.

Lead the analysis

Now, a problem driven structure might ensure that we eventually generate a solution, but how do we actually get there? We call this step "leading the analysis", and is the process whereby you systematically navigate your structure, identifying the key factors which are driving the issue we are addressing.

Generally, this will mean continuing to grow your tree diagram, further segmenting what you identify as the most salient end nodes to drill down into the most crucial factors causing the client’s central problem. Once you have gotten right down into the detail of what is actually causing the company’s issues, solutions can then be generated quite straightforwardly.

To see this process in action, we canreturn to our airline revenue example. Let’s say that we discover the average ticket price to be a key issue in the airline’s problems. We then look closer at the drivers of average ticket price and find that the problem lies with Economy Class ticket prices. We can then further segment that price into the base fare and additional items such as food. Having broken down the issue to such a fine-grained level, solutions occur quite naturally. In this case we can suggest incentivizing the crew to increase onboard sales, improving assortment in the plane or offering discounts for online purchases.

Lead the Airline Case Study

Our article on leading the analysis is a great primer on the subject, with our video lesson in the MCC Academy providing the most comprehensive guide.

Provide recommendations

You might have arrived at a solution, but you aren’t finished yet! Now you need to deliver that solution as a final recommendation. This should be delivered as if you are briefing a busy CEO and thus should be a one minute, top-down, concise, structured, clear and fact-based account of your findings .

The brevity of the final recommendation belies its importance. In real life consulting, the recommendation is what the client has paid thousands for - from their point of view it is all that matters. In an interview, how you perform this final summing up of your case is going to significantly colour your interviewer’s parting impression of you - and thus your chances of getting hired!

So how to we do it right? Barbara Minto's Pyramid Principle elegantly sums up almost everything that required from a perfect recommendation. The answer comes first, as this is what is most important. These are the then supported by a few key arguments - which are in turn buttressed by supporting facts. Across the whole recommendation, the goal is not simply to summarise what you have done, but rather to synthesise your findings so as to extract the key "so what?" insight that will actually be useful to the client going forward.

All this might seem like common sense, but it is actually the opposite to the way we relay results in academia and other fields; where we typically move from data through arguments and eventually to conclusions. As such, making good recommendations is a skill which will take practice to master.

We can see this principle illustrated in the diagram below:

The Pyramid principle often used in consulting

To this scheme, we suggest candidates add a few brief remarks on potential risks and suggested next steps . This helps demonstrate ability for critical self-reflection and lets your interviewer see you going the extra mile.

In the final recommendation in particular, the combination of logical rigour and communication skills which are so definitive of consulting are on full display. Despite it only lasting 60 seconds, to deliver a really excellent recommendation and leave your interviewer with a good final impression of your case solving abilities, you will need to leverage a full set of key consulting skills. Our specific article on final recommendations and the specific video lesson on the same topic withing our MCC Academy are great, comprehensive resources, but our lesson on consulting thinking and our articles on MECE and the pyramid principle are also very useful.

Building blocks

Now, the whole case cracking method we have set out thus far emphasises starting from first principles to develop a fresh approach to each and every case question you are presented with. However, since we have also identified a number of common topics popping up in case interview questions, you might well ask if we really need to spend the time required to work up from first principles in every single case. Indeed, this is what the case interview frameworks promoted elsewhere will claim to do for you – to save you precious time by zeroing in on the kind of question you have been asked.

This is where we introduce our Building Block concept. We have devised modular building blocks to capture the commonalities between cases identified in each of the five key topics outlined above. These building blocks are designed as modular, off-the-peg elements which allow you to leverage the symmetries between different cases to structure problems more quickly and effectively.

Now, building blocks might ostensibly sound a lot like the case interview frameworks we have railed against above. “Generic solutions to a small set of case types? Sounds just like Case in Point!” However, this is not so. Indeed, we can introduce the unique features of building blocks by considering exactly how they differ from old-fashioned frameworks.

Framework-based approaches identify a set of strictly-defined case types and then provide a single generic scheme for each — apparently able to solve all instances of that case type. By contrast, building blocks embrace the infinite variety and complexity of cases and the fact, as noted above, that the different question themes we have identified can all run into one another.

Building blocks do not claim to capture the entirely of any one case and intend only to provide a strong starting point when you encounter each of these question topics, rather than to dictate your approach right from A to Z. Think of frameworks as a flatpack, fibreboard coffee table from Ikea. It might be quick to assemble, but it’s only good for one thing and might get shaky under pressure. Our building blocks are more like standard planks of wood. You can use them to make multiple different structures and the end product is going to be sturdy and reliable.

We noted above how different topics can easily overlap in the same case interview question — with the example that a pricing decision might affect how a company competes with other market players, which will in turn affect profitability and valuation. Overlapping topics mean that it is quite natural to structure a case with the deployment of two or more building blocks. Thus, we might well address a company’s profitability concerns by analysis of that company’s pricing strategy, making use of both corresponding building blocks as we structure our approach to the overarching problem. In particular, we can expect to have to make estimations as part of pretty well any case interview question, so this is a building block which we will leverage constantly.

Frameworks would not have survived for so long if they didn’t latch onto something useful. Our Building Blocks allow you to retain the time-saving benefits of frameworks, but without inheriting their fatal flaws in terms of inflexibility.

Let's take a look at our five key building blocks below, with a brief introduction to how you might use each.

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Estimation

Estimation questions can often seem very daunting on first impression. Where would we even start in working out how many cars are sold in Berlin, for example? The key to estimation case questions is the ability to logically break down the problem into more manageable pieces. In consulting case studies, this will generally mean segmenting a wider population to find a target group. For example, starting from the total population of Berlin and narrowing down on the cohort of individuals which will buy a car that year.

There are many ways to segment the same starting population. However, whilst several different segmentation schemes might be equally valid, it is crucial to choose the specific method best suited to the question you have to answer and to leveraging the data you have available.

Segmentation must be allied with assumptions in order to arrive at an estimation. These assumptions are the “guessed” element of estimations we mentioned above. Assumptions cannot just be plucked from thin air, but must always be reasonable.

The example below showcases both the segmentation and assumptions made in an estimation of the size of the wedding planning market in London:

Estimation Example Structure

Our articles here on the MECE concept and estimation are great starting points in learning the relevant skills to make estimations in consulting case questions. However, the best place to learn how to make estimations is with the dedicated building block video lesson in our MCC Academy course.

Profitability

Understanding profitability ultimately means understanding the various components which go to determine the profit of a company. Thus, you will learn to decompose profit first into the revenues and costs of which it is the synthesis and then — crucially — to further segment, distinguishing different revenue streams and separating various fixed and variable costs.

To take an example, just to take revenues as a fraction of profit, the incoming revenues for an insurance firm might be broken down as follows:

Insurance Revenues

Taking steps to improve profitability will inherently mean increasing revenues and/or decreasing costs. To solve profitability problems, we will thus have to understand the various means at our disposal to minimise different forms of cost as well as ways to drive sales or optimise pricing to increase revenue. Importantly, you must be able to judge which of these options is best suited to addressing different scenarios.

The key to tackling the complex kind of profitability questions given by MBB-level consultancies lies in proper segmentation. Many old-fashioned case interview frameworks will simply have you look at aggregate cost and revenue data and then simply have you recommend generic cost-cutting or revenue-driving measures based on that. However, this will often lead to negative outcomes, making matters worse for our client company.

For example, it might well be that a company makes a loss when it serves a certain cohort of customers. An airline, for instance, might be losing money on economy class customers but making a healthy profit on each business class customer. Attempts to boost revenue by increasing sales generally might actually have suppressed profit further by increasing the number of economy class customers. What is required is targeted measures to increase focus on business class and/or mitigate economy class losses.

You can start to learn more about how to segment these questions properly, as well as getting to grips with the other ideas mentioned here, in our article on profitability, with the best way to master profitability being our full lesson on the subject in the Building Blocks section of our MCC Academy course.

Pricing

To understand pricing, you will need to begin from the fundamentals of ideas like the customer’s willingness to pay, the value captured by the company and the value created for the customer. These basics are shown in the diagram below:

Pricing Basics

This might seem simple enough, but the exact level at which prices are set is determined by a whole host of factors, including product availability, market trends and the need to maintain a competitive position within the market. If we are changing the price of an existing product, we must consider how price elasticity of demand might cause sales to fluctuate in the face of altered prices.

Our four-step method for pricing starts from establishing the customer’s next best alternative, working out the value added by our own product and working from there. A summary of this method is given, along with an overview of pricing in general, in our article on the subject . The most complete resource, though, is our pricing building block lesson in the MCC Academy.

Valuation

There are multiple different ways of calculating value. These include asset-based valuations and the multiples method. In consulting case interviews, though, you will generally refer to Net Present Value (NPV). Thus, you will need to master the NPV equation:

NPV Equation

Where:

CF = Cash Flow
r = Discount Rate

However, NPV is far from the last word in valuation. The fact is that the worth of any asset will be different for different buyers, depending upon what the buyer already owns. In just the same way spare clutch for a 1975 Ford will hold much more worth to someone restoring the relevant classic car than to a cyclist, so a courier business will be more valuable to an online retailer than to an airline.

As such, what we call the Total Enterprise Value (TEV) of an asset is calculated as a function of that asset’s NPV and of the potential cost and revenue synergies which pertain from making any acquisition. This is shown in the useful structure below:

TEV

In order to grasp valuation and investment, you will also need to develop a feel for interest/discount rates. This will be essential, as you will often have to estimate rational values for these rates for different investments (and then plug those values into the NPV equation).

You can more about all aspects of valuation in our article here and in our dedicated video lesson in MCC Academy. These include guides to the kind of interest rates which would typically be required for financing different kinds of investment.

Competitive Interactions

Your eventual solutions as to how a company should react to a changing market might be highly creative and sweeping in their prospective effects. However, the process by which we understand competitive interactions and thus move towards such solutions is typically highly systematic — indeed, algorithmic - as we move through the limited dimensions in which it is possible for a company to take action. The following structure neatly encodes the general options open to responding to new sources of competition:

Competitive Interaction Structure

Of course, we would never suggest that you blanket-apply any strict, inflexible methodology to a whole swathe of case questions - this is precisely the approach that causes so much trouble for candidates using old-fashioned frameworks.

This structure is only a starting point — a shortcut to a bespoke framework, specific to the case question in hand. You might have to alter the details of the structure shown and you will almost certainly have to expand it as you lead the analysis. How you lead the analysis and the solutions you provide are necessarily going todepend wholly upon the specific details of the case question.

Thus, in order to deal with competitive interactions, you will need to put in the time understanding how the different strategies available function — as well as how competitors might then react to implementing such strategies. With enough practice, though, soon you won’t be fazed by even the most complex cases of competition between firms. Learn more in our article here and in our dedicated video lesson on competitive interaction in the MCC Academy case interview course.

Analysis tools

Companies hire consulting firms for their problem solving and communication skills. These are the same skills which in turn will get you hired by McKinsey, BCG or Bain! This is the reason why consulting thinking is a pillar of our method. Principles such as MECE or the 80/20 rule are ubiquitous in consulting, and mastering them makes the difference between an average and a top candidate. The distinctive characteristic of a management consultant is that they have a problem solving mentality. In particular, they focus on generating solutions to problem using a fact-based approach. This approach relies on 5 key elements:

  • MECE structures
  • Root cause analysis
  • An Hypothesis driven mentality
  • Fact based "so what's"
  • 80-20 rule

These elements are intrinsically linked; our course elaborates on each in detail.

Relationship among different elements of consulting thinking

Problem driven structure vs frameworks

As we have noted previously, old-fashioned case interview frameworks (as found in Case in Point and Case Interview Secrets) are unreliable and will not impress your interviewer. This might be a bitter pill to swallow if you have already waded through the relevant books and devoted time to rote learning these frameworks.

However, on reflection, the simple fact that using frameworks is indeed a matter of rote learning should be a huge red flag in itself. We can think about this from a couple of angles — let’s take a closer look!

Frameworks are inflexible

Rote learning solutions pre-supposes that the cases you encounter in future will conform to the same basic mould as the previous cases those solutions were derived from. When you use a framework to tackle a case study, you typically begin by selecting a case type with regards to a few variables such as topic (profitability, M&A, market entry) interviewer stance, company etc. You then select the relevant framework and do the calculations recommended. Crucially, the frameworks are very fixed and do not allow for significant customisation to accommodate unique features of problems. Frameworks rely on cases neatly dividing into distinct types, where each instance of a particular type is very much like the others.

However, and very unfortunately for the candidates that rely on them, this means that case interview frameworks will struggle with precisely the kind of question which are likely to come up in consulting interviews . There is a reason no working consultant ever uses frameworks!

As is well known, consulting case interview questions tend to be based on a real project the interviewer has been working on recently. Consultants are engaged by their clients to solve unique problems, which have proved resistant to standard solutions (otherwise the client would have saved tens of thousands and dealt with the issue in-house). Thus, consulting case interview questions are going to be based on precisely the kind of unique problems that have refused to fit into standard frameworks or other off-the-peg solutions. Since frameworks do not have the flexibility to cope with these more complex scenarios, the unlucky candidates making use of them will simply be stumped. Despite all their hard work in preparation — and hours of rote learning — they will wash out of their case interview and will not be hired.

Case interviews assess individual reasoning

So, we have considered the demands of the question, but we should also consider the intention behind posing case questions. Remember that the whole point of case interviews is to assess the candidate's ability to think on their feet and come up with creative solutions to new problems . If consultancies wanted to simply test memorised knowledge, it would be a lot cheaper for them to set written tests, rather than divert working consultants to act as interviewers.

Given all this, an interviewer is not going to be impressed by you parroting the same script they have already heard from the past five candidates who were also using the same framework (doubly so as that framework probably hasn’t worked for the case they set). Consulting firms are simply not interested in hiring candidates who distinguish themselves only by learning a dozen generic recipes!

Comparison between Problem Driven Structure and Framework approach

Flexible problem solving: working from first principles

Our innovative problem driven structure approach takes a radically different approach to old-fashioned frameworks. For one thing, there are no generic sets of instructions to be precisely applied. Rather, we teach a set of skills with guidelines on how to apply those skills flexibly to any new problem. Indeed, our method was derived as a streamlined version of the seven step system used by McKinsey consultants on real engagements.

The first step of our method is always to understand the case you have been given in detail and on its own merits . From here you draw up a unique problem driven structure — which you can think of as building your own new framework for each individual question.

Clearly, this solves the problem of inflexibility which lets down candidates attempting to apply old-fashioned frameworks to unique, irregular cases. By contrast to such limitations, problem driven structures - as a method for approaching issues from first principles - is sufficiently general that it can even be applied well outside the realms of business problems.

With the MCC approach, rather than rote learning a set of generic scripts, you learn genuine consulting skills and how to apply those to novel problems in just the same manner as would a working consultant. Far from being frustrated by watching a candidate operating on autopilot, your interviewer will be genuinely impressed to see you clearly tackle the case they have set using the same methods they would themselves. As an indicator of the value of our approach, not only does prepping our way increase your chance of being hired, but it also let’s you hit the ground running on day one of the job itself, as you are already with the fundamental skills leveraged in real consulting work. No real consultant uses frameworks, but all are united in applying those same methods and principles built into the problem driven structure approach and taught in our MCC Academy course.

You can learn more about why frameworks are unreliable and how our method works in this video:

Now, let’s take a break from all this theory and learn more about how case interviews work in real life.

What is it like in practice? Putting it all together...

Of course, all this theory is well and good, but a lot of readers might be concerned about what exactly to expect in real life. It’s perfectly reasonable to want to get as clear a picture as possible here - we all want to know what we are going into when we face a new challenge!

Indeed, it is important to think about your interview in more holistic terms. One theme here is that getting the mechanics of analysis and getting the exact right answer is less important than the approach you take to reasoning and how you communicate — candidates often lose sight of this fact.

In this section, then, we’ll run through the case interview experience from start to finish, directing you to resources with more details where appropriate. As a supplement to what we say here, the following video from Bain is excellent. It portrays an abridged version of a case interview, but is very useful as a guide to what to expect - not just from Bain, but from McKinsey, BCG and any other high-level consulting firm.

Getting Started

Though you might be shown through to the office by a staff member, usually your interviewer will come and collect you from a waiting area . Either way, when you first encounter them, you should greet your interviewer with a warm smile and a handshake (unless they do not offer their hand). Be confident without verging into arrogance. You will be asked to take a seat in the interviewer’s office where the interview can then begin.

First Impressions

In reality, your assessment begins before you even sit down at your interviewer’s desk. Whether at a conscious level or not, the impression you make within the first few seconds of meeting your interviewer is likely to significantly inform the final hiring decision (again, whether consciously or not). Your presentation and how you hold yourself and behave are all important. If this seems strange, consider that, if hired, you will be personally responsible for many client’s personal impressions of the firm. These things are part of the job! Much of material on the fit interview is useful here, whilst we also cover first impressions and presentation generally in our article on what to wear to interview.

As we have noted above, your interview might start with a fit segment — that is, with the interviewer asking questions about your experiences, your soft skills and motivation to want to join consulting generally and that firm in particular. Basically, the kinds of things which a case study can’t tell them about you. We have a fit interview article and course to get you up to speed here.

Down to Business

Following any initial conversation, your interviewer will introduce your case study, providing a prompt for the question you have to answer. You will have a pen and paper in front of you and should (neatly) note down the salient pieces of information (you should keep this up throughout the interview).

It is crucial here that you don’t delve into analysis or calculations straight away. Case prompts can be tricky and easy to misunderstand — especially when you are under pressure. Rather, ask any questions you need to fully understand the case question and validate that understanding with the interviewer before you kick off any analysis. Better to eliminate mistakes now than experience that sinking feeling of realising you have gotten the whole thing wrong half way through your case!

This process is covered in our article on identifying the problem and in greater detail in our MCC Academy lesson on that subject.

Analysis

Once you understand the problem, you should take a few seconds to set your thoughts in order and draw up an initial structure for how you want to proceed. You might benefit from utilising one or more of our building blocks here to make a string start. Present this to your interviewer and get their approval before you get into the nuts and bolts of analysis.

We cover the mechanics how to structure your problem and lead the analysis in our articles here and here and more thoroughly in the MCC Academy. What it is important to convey here, though, is that your case interview is supposed to be a conversation rather than a written exam . Your interviewer takes a role closer to a co-worker than an invigilator and you should be conversing with them throughout.

Indeed, how you communicate with your interviewer and explain your rationale to them is a crucial element of how you will be assessed. Case questions in general are not asked to see if you can produce the correct answer, but rather to see how you think. Your interviewer wants to see you approach the case in a structured, rational fashion. The only way they are going to know your thought processes, though, is if you tell them!

To demonstrate this point, here is another excellent video from Bain, where candidates are compared. Note that multiple different answers to each question are considered acceptable, but that Bain are concerned with the thought processes the candidates exhibit.

Another reason why communication is absolutely essential to case interview success is the simple reason that you will not have all the facts that you need to complete your analysis at the outset. Rather, you will frequently have to ask the interviewer for additional data to allow you to proceed.

Don’t be let down by your math!

Note that your ability to quickly and accurately interpret these charts and other figures under pressure is one of the skills which is being assessed. You will also be required to make any and all calculations that are required quickly and accurately (and without a calculator!). As such, you should be sure that you are up to speed on your consulting math.

Recommendation

Finally, you will be asked to present a recommendation. This should be delivered in a brief, top-down "elevator pitch" style format, as if you are speaking to a time-pressured CEO. Again here, how you communicate will be just as important as the details of what you say. Speak clearly and with confidence and take a look at our articles on the pyramid principle and providing recommendations, as well the relevant lesson within MCC Academy, for more detail on how to give the perfect recommendation.

Wrapping Up

After your case is complete, there might be a few more fit questions — including a chance for you to ask some questions of the interviewer. This is your opportunity to make a good parting impression — we deal with the details in our fit interview resources.

It is always worth bearing in mind just how many candidates your interviewers are going to see giving similar answers to the same questions in the same office. A pretty obvious pre-requisite to being considered for a job is that your interviewer remembers you in the first place. Whilst you shouldn't do something stupid just to be noticed, asking interesting parting questions is a good way to be remembered.

Now, with the interview wrapped up it is time to shake hands, thank the interviewer for their time and leave the room. You might have other interviews or tests that day or you might be heading home. Either way, if know that you did all you could to prepare, you can leave content in the knowledge that you have the best possible chance of receiving a call with a job offer. This is our mission at MCC — to provide all the resources you need to realise your full potential and land your dream consulting job!

4 steps for an effective case interview preparation

Too many candidates try to steam ahead into their preparation without having made any kind of plan to guide their efforts. As a result, they will spend their time inefficiently and end up with a patchy case interview prep.

Impress your interviewer

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To plan effectively, you first need to know what you are preparing for. As noted, consulting interviews have two sections: Fit and Case. Both are equally important, and to get hired you must be successful in both.

1. Learn the theory

The MCC Academy is a comprehensive, all-in-one package, teaching you everything you need to know about the case interview. We designed the course around a sensible suggested structure for a candidate with little business background. While following that structure is the simplest course of action, a more experienced candidate can easily adapt it to their specific needs. Your case interview preparation approach depends on:

  • Background: whether you are new to consulting case interviews or not will affect the amount of background reading you need to do. In any case, you will need to learn about our problem driven structure approach.

  • Timeframe: clearly time will affect you preparation. We usually advise our clients to prepare for around 60 hours, obviously the more practice you get the better it is. For the mathematically inclined, time invested vs return approximates an S-curve.

2. Solo practice

For solitary preparation, perhaps one of the best uses of your time is to work on your mental mathematics. This skill is neglected by many applicants - much to their immediate regret in case interview. Find our mental math tool here or in our course and practice at least 10 minutes a day from day one to the day before the interview. Once you covered our Building Blocks (week 2), then you should start working through the cases in My Consulting Coach's case bank alongside your work on the course. This is a large and frequently updated source of case interview questions and answers. To build your confidence, start out on easier case questions, work through with the solutions and don't worry about time. As you get better, though, you can move on to more difficult cases and try to get through them more quickly. You should practice around 8 case studies on your own to build your confidence.

3. Practice with a case partner

Regardless of your background, you will need to put in significant time practicing cases. Solitary practice is useful, but your case interview prep will only progress so far without actually simulating the case interview. As such, finding good case partners is perhaps the single most important aspect of your preparation. To help you out here, My Consulting Coach offers an intuitive, user-friendly and - importantly - FREE meeting board, where you can get in touch with fellow consulting applicants from across the globe with whom to practice case studies. Candidates are listed along with their background and case experience and the board has easy-to-use tools for both direct invitations and scheduling open meetings.

We recommend you to practice 1-3 cases per day with peers depending on your available time. You can start doing so once you have covered our Building Blocks (week 2), to then ramp up your practice when you have completed the course and have more time (week 4 onwards according to our schedule). My Consulting Coach provides 45+ interactive consulting case interview questions and answers for you to crack with your partners, so you will have plenty to keep you busy! Two tips:

  • Practice with as many different case partners as possible: the more different perspectives you get on how you work, the more you’ll be able to get feedback and fine-tune your performance

  • Don’t neglect the part of the part of the session where you play the interviewer role: stepping into the interviewer's shoes will help you get their perspective and help you understand both what they are looking for and how they assess it.

4. Expert help

This step is optional, but profoundly useful. The most effective way to conduct your consulting case interview prep will always be to get help from someone who has worked as a consultant for a top firm. Nobody else will be able to spot your weaknesses so quickly or offer better advice to deal with them.

Of course, you will never be able to secure the time of these individuals for free. However, it is worth considering the difference in your salary over even a just few years between getting into a top tier firm versus a second tier one. In the light of thousands in increased annual earnings (easily accumulating into millions over multiple years), it becomes clear that getting expert help is one of the best investments you can make for your own future.

Should you decide to make this step, My Consulting Coach can help, offering the highest quality case interview coaching service available. Each MCC case coach is selected as an ex-MBB consultant with two or more years of working experience and strong coaching expertise.

Case interview coaching is hugely beneficial in itself. However, for those who want to genuinely maximise their chances of securing a job offer - and especially for time-poor, busy professionals who want to take the guesswork and wasted time out of their case interview prep - we also offer a much more comprehensive service.

With one of our "springboard" bespoke mentoring programs, you are paired with a mentor from your target firm, who will then oversee your whole case interview preparation from start to finish. After an initial consultation to assess your existing capabilities, your mentor draws up a fully personalised plan to get you interview-ready as efficiently as possible. This plan will leverage material from right across the full gamut of learning resources MCC produce - to which you will have complete access to (including our MCC Academy course). Your mentor will then arrange all the case interview coaching sessions needed to get you fully up to speed. All the while, your mentor will monitor your progress, ammending your preparation plan as neccessary and generally never being more than a phonecall or an email away to answer questions and provide recommendations.

The outcome is that you will be able to throw yourself into your case interview prep in the knowlegde that you are moving towards your goal as quickly as possible. Rather than the typical case interview prep experience of trawling dodgy websites, forums, reddit etc for whatever advice you can find and then trying to work out which pieces of mutually contradictory information are actually true, you will be able to devote all that time and mental energy to a successful preparation.

The results of our mentoring service speak for themselves. Candidates completing our Springboard program enjoy an unparalleled 75%+ success rate. If you are a busy student, balancing exams with consulting applications, or a hard-pressed professional who already works long hours, then check out our mentoring programs as the best way to walk out ouf your consulting interviews without regrets.

A final note: track your progress

At My Consulting Coach, we strongly believe that mistakes can be your most valuable source of progress. After every case interview coaching session with with us, you will receive our Performance Radar. This written report combines your case coach's feedback with scores generated via our statistical modelling which break down your performance across all the key area of Problem Solving, Structure, Communication, Numerical Agility. These scores allow you to track your progress quantatively; pinpointing those areas where you should focus your efforts as well as those where you have improved. This advanced feedback system ensures that you are always in control.

Fit Interview

Most candidates spend their time on case interview preparation and neglect their fit interviews. This is a major problem, as both these components of the selection process are accorded equal importance by recruiters and good performance in one will not make up for a poor showing in the other. The bottom line is that consultancy firms simply will not employ someone who they doubt will be a good fit with the company, regardless of how many cases they can crack.

The fit interview will be especially important if you are coming into consulting via a less standard route. You will need to be able to provide a compelling narrative to explain why, even though you are coming from elsewhere, consulting is the right move for you at this point in your career, as well as how your previous experiences have furnished you with the relevant skills for consulting.


Find out more in our case interview course

Ditch outdated guides and misleading frameworks and join the MCC Academy, the first comprehensive case interview course that teaches you how consultants approach case studies.