Case interviews are at the heart of the selection process at top consulting firms. In practice, they test whether candidates have the analytical horsepower to solve strategic problems.
Candidates often find case interviews to be challenging and intimidating. They require a high level of skill and preparation to structure, calculate, synthesize, and conclude.
In this article, we’ve outlined what a case interview looks like, how to succeed in these types of interviews, and how to properly prepare.
- Understanding the case interview
- What case study interviews assess
- The most common case study interview questions
- How are case study interviews delivered
- Where to watch a case interview videos
- What a good structure looks like
- Using frameworks to structure consulting cases
- The most popular frameworks for structuring cases
- How to prepare for a case interview
Understanding the case interview
From the client’s brief, through the analyses, all the way to the recommendation, case interviews simulate the job of a management consultant. Top consulting firms use the case interview as it’s a statistically-proven predictor of how well a candidate will do on the job.
Case Study Interviews are normally delivered one-on-one, last around 30 minutes, and follow five steps. They are:
- The interviewer gives the brief for the case. They explain the context the organization in the case is operating in and the challenges that they’re facing.
- The candidate then has a chance to ask clarifying questions, perhaps to test or confirm an understanding of the context or of the problem itself.
- The candidate takes around 30 seconds to reflect and lay out a structured approach to solving the case.
- The interviewer and the candidate work through the case together, carrying out analyses and ultimately driving towards a recommendation. This is the part of the case where the candidate will be handling numerical questions, reviewing exhibits, and coming up with creative ideas. It comprises the majority of the time spent on the case.
- The candidate synthesizes their findings and makes an overall recommendation.
What case study interviews assess
While the primary purpose is to assess candidates’ problem-solving skills, case study interviews also provide a read on whether candidates have the presence and communication abilities necessary to give a positive and professional impression.
Interviewers use scorecards that track key problem-solving dimensions to assess a candidate’s performance in these areas. They include:
- Structuring – The ability to break down the problem into smaller manageable chunks
- Numeracy – The ability to do basic math on paper
- Judgement and Insights – The ability to draw conclusions from facts
- Creativity – The ability to generate ideas
- Synthesis – The ability to summarize the work into an actionable recommendation
- Case Leadership – The ability to drive the discussion towards the recommendation
Additionally, if a candidate is interviewing for a role focused on a specific industry or function, their expertise in that area might be assessed as part of the case.
The most common case study interview questions
Case study interview questions generally mirror the work of the employer.
If a candidate is interviewing for a role that is focused on a specific industry or function, such as technology, it’s necessary to have researched the typical projects that might be worked on and their respective solutions. These types of problems will likely come up during the case interview.
If a candidate is interviewing for a generalist role, they should get familiar with the most common business questions faced by CEOs, and their approaches to solving them. Consultants at top consulting firms are commonly involved in solving these questions and they often tend to come up in business case interviews. The questions include:
- Improving profit
- Growing a business
- Reducing costs
- Entering a new market
- Launching a new product
- Pricing a product
- Acquiring a new business
- Deciding on an investment
- Responding to a competitive threat
- Optimizing a process
However, to avoid candidates gaming the system, the top-tier firms are moving away from the more common types of cases. London Business School MBA students reported that a third of the case study interview questions they saw when interviewing with top consulting firms did not fall within any of the above question types.
How are case study interviews delivered
A consulting case interview can feel like a role play, where the interviewer plays the role of a Manager or a Client and the candidate the role of the Analyst or Consultant hired to solve the problem. However, the interview should not feel like a performance, rather it should feel like a natural conversation between two people.
Although consulting case study interviews have a set format, they can be delivered in different ways. Some can be candidate-led and others can be interviewer-led:
- In a candidate-led case, the candidate is free to explore different aspects of the problem. The interviewer will not tell the candidate explicitly what to focus on, rather, they will provide additional information when needed, such an exhibit or a few new facts. It’s then expected that the candidate will analyze this information and suggest the next steps to get to the answer.
- In an interviewer-led case, the candidate also suggests next steps, but the interviewer may interrupt and ask the candidate to focus on a specific question or aspect of the case. In an interviewer-led case, candidates are less likely to take the wrong path.
Regardless of how a case is led, the candidate is expected to suggest next steps after every analysis and to have a view about how to get to the answer.
Where to watch a case interview video
In the video below, two former management consultants demonstrate a real case interview using an investment case named FlashFash. It includes helpful feedback on how the candidate is doing during the case.
To get a PDF copy of the FlashFash case, log in to the Interview Prep Course and download the case library.
What a good structure looks like
Structuring is among the most difficult parts of the consulting case interview. While there isn’t just one correct structure for a case interview question, there are many wrong ones.
A good structure needs to focus on the right question, break it down into an exhaustive set of independent drivers, provide an approach to solving the case, and supply helpful insights.
A common approach to ensuring a good structure is the AIM test (Answer-focused, Insightful, and MECE). To expand upon this:
- Answer-focused means two things in practice: the structure focuses on the right question and it provides an approach to answering that question.
- Insightful means the structure is tailored to the specifics of the client or problem in the case and that it is not generic. If the structure can be applied to another case of a similar type, then it hasn’t passed the Insightful test.
- Mutually Exclusive and Collectively Exhaustive, or MECE means that the drivers outlined in the structure are exactly as such. Mutually Exclusive means that the drivers in the structure are independent and don’t overlap; they can be handled separately, or in turn. Collectively Exhaustive means that when combined, the drivers in the structure are comprehensive enough to answer the case question.
Using frameworks to structure consulting cases
Thirty years ago, people started to use frameworks to structure cases, as was popularized by the book “Case in Point”. Another book, “Case Interview Secret”, went further by suggesting that most consulting cases could be solved using a single “one-size-fits-all” framework.
Unfortunately, candidates who depend on these books today are being led down the wrong path. Top consulting firms are increasingly using unusual case questions that do not simply fit neatly into a generic framework. A candidate needs to demonstrate to an interviewer that they are capable of strongly structuring a case, as opposed to just relying on a framework.
Although frameworks should not be memorized and applied as is, knowing them can be a good starting point and source of inspiration when crafting bespoke consulting case study structures.
The most popular frameworks for structuring consulting cases
Here are the five most popular frameworks candidates should know:
This is the mother of all case interview frameworks as there’s a high chance that some form of a profit problem will come up during multiple rounds of consulting interviews.
Simply put, it consists of breaking down profits into revenue and cost. Revenue is the quantity sold multiplied by the price of the product and cost is the sum of all the fixed and variable costs. Increasing profit will require moving these drivers in the right direction.
2.Porter’s Five Forces
Porter’s Five Forces helps assess whether an industry is attractive given the competitive forces at play. It’s a good tool to use when considering whether to enter a new market:
The five forces are:
- New Entrants
A company is unlikely to be profitable if its industry has few potential customers, is dominated by a small number of competitors, has substitutes readily available, experiences many new entrants, or where critical resources are controlled by powerful suppliers.
The 4Ps framework, or “Marketing Mix”, is often used to establish an effective strategy for launching a new product to the market. For a strategy to be effective, the four components of the marketing mix need to be aligned. They are:
- Product (i.e. features, quality, design, packaging, after-sales service)
- Promotion (i.e. advertising plan)
- Place (i.e. geographies and distribution channels)
The Boston Consulting Group (BCG) Matrix, or growth-share matrix, is a framework that helps businesses prioritize where to focus to maximize their growth and shape their strategy. It classifies businesses into four categories based on the growth of the industry and the relative market share. They are:
- Dogs – Low market share in a slow-growing market. These should be discarded.
- Cash Cows – High market share in a slowly growing market. These are profitable and should be milked (i.e. managed to maximize profitability).
- Stars – High market share in a fast-growing market. These should be invested in, to create tomorrow’s Cash Cows.
- Question Marks – Low market share in a fast-growing market. The company should decide whether to discard or to build up into a Star.
5.Victor Cheng’s Business Situation Framework
This framework is meant to be a one-size-fits-all approach to solving business case questions when entering a new market, launching a new product, growing revenue, or establishing a strategy.
The four factors it lists to analyze are:
Unlike the other frameworks in this list, the Business Situation Framework does not have an overarching logic that helps candidates make a recommendation. It’s more of a list of important factors to bear in mind.
How to prepare for a case interview
Case study interviews are no easy ride, but candidates can give themselves the best chance of success by dedicating time to prepare for case interviews.
It is generally accepted that it takes 60+ hours of preparation to truly master consulting case interviews. Here’s how successful candidates spend this time:
1. They practice cases
While it might be cliched, ‘practice makes perfect’ is true concerning consulting case interviews.
It takes at least 25 live case interview practices, as both the interviewer and candidate to reach a good level of case proficiency. Playing both roles of the interview is useful in learning best practices from others.
To make the most of case study interview prep time, candidates should use:
- The interview scorecard, like one used by top consulting firms, that assesses all the dimensions of the case study interview
- High-quality case interview examples that closely resemble the ones in real interviews, test the right skills, and where top-mark answers are provided
- Good case partners who can deliver a case well and provide useful feedback
You can download our interview scorecard and our case library in the Interview Prep Course.
2.They learn the theory
Practicing case interviews is essential, as is understanding the theory behind them and learning the best techniques to solve cases effectively.
Once a candidate has done at least a few live case interview practices, they should begin to learn the theory behind what it takes to complete a great case interview. This is all covered in the Interview Prep Course.
We also recommend watching videos of interviews where feedback is given on how well the interviewee does, so it’s clear what a great case interview looks like in practice. You will find such videos in the Interview Prep Course as well.
3.They develop key skills
It is unlikely that someone will get a job in a top consulting firm just by having exceptional numeracy skills, but it is likely someone won’t get the position if they don’t have them.
Unless candidates are using math in life day-to-day, it is always helpful to brush up on mental math skills and to do a number of drills every day to ensure that these skills are in the best shape possible when going into a consulting interview.
Structuring and drawing insights from exhibits are two other key skills that must be mastered to avoid receiving a rejection. Similar to numeracy, these skills can be practiced in isolation outside of a case interview.
The Interview Prep Course provides math, structuring, and exhibit drills to practice these key skills.
For candidates who don’t have a business or economics background, keeping an eye on the latest business news is also helpful in improving business acumen. Asking “How did the CEO make that decision?” each time a business update is released is a helpful way of building the ability to structure consulting cases.
4.They get good feedback
Too many candidates waste time practicing cases and receiving feedback from people who don’t know what great looks like for case interviews.
The speed and ability to improve case solving skills are directly correlated with the quality of feedback received. It is important to practice with and to receive feedback from people who know what to look for.
It’s possible to do this by practicing cases with other candidates and with current and former consultants.
Implementing the four strategies outlined here – practice, learning the theory, developing the skills, and soliciting high-quality feedback – will put any candidate well on their way to succeeding in their consulting interviews.