mbb case study prep

47 case interview examples (from McKinsey, BCG, Bain, etc.)

Case interview examples - McKinsey, BCG, Bain, etc.

One of the best ways to prepare for case interviews at firms like McKinsey, BCG, or Bain, is by studying case interview examples.

There are a lot of free sample cases out there, but it's really hard to know where to start. So in this article, we have listed all the best free case examples available, in one place.

The below list of resources includes interactive case interview samples provided by consulting firms, video case interview demonstrations, case books, and materials developed by the team here at IGotAnOffer. Let's continue to the list.

McKinsey examples
BCG examples
Bain examples
Deloitte examples
Other firms' examples
Case books from consulting clubs
Case interview preparation

Click here to practise 1-on-1 with MBB ex-interviewers

1. mckinsey case interview examples.

Beautify case interview (McKinsey website)
Diconsa case interview (McKinsey website)
Electro-light case interview (McKinsey website)
GlobaPharm case interview (McKinsey website)
National Education case interview (McKinsey website)
Talbot Trucks case interview (McKinsey website)
Shops Corporation case interview (McKinsey website)
Conservation Forever case interview (McKinsey website)
McKinsey case interview guide (by IGotAnOffer)
Profitability case with ex-McKinsey manager (by IGotAnOffer)
McKinsey live case interview extract (by IGotAnOffer) - See below

2. BCG case interview examples

Foods Inc and GenCo case samples (BCG website)
Chateau Boomerang written case interview (BCG website)
BCG case interview guide (by IGotAnOffer)
Written cases guide (by IGotAnOffer)
BCG live case interview with notes (by IGotAnOffer)
BCG mock case interview with ex-BCG associate director - Public sector case (by IGotAnOffer)
BCG mock case interview: Revenue problem case (by IGotAnOffer) - See below

3. Bain case interview examples

CoffeeCo practice case (Bain website)
FashionCo practice case (Bain website)
Associate Consultant mock interview video (Bain website)
Consultant mock interview video (Bain website)
Written case interview tips (Bain website)
Bain case interview guide (by IGotAnOffer)
Digital transformation case with ex-Bain consultant
Bain case mock interview with ex-Bain manager (below)

4. Deloitte case interview examples

Engagement Strategy practice case (Deloitte website)
Recreation Unlimited practice case (Deloitte website)
Strategic Vision practice case (Deloitte website)
Retail Strategy practice case (Deloitte website)
Finance Strategy practice case (Deloitte website)
Talent Management practice case (Deloitte website)
Enterprise Resource Management practice case (Deloitte website)
Footloose written case (by Deloitte)
Deloitte case interview guide (by IGotAnOffer)

5. Accenture case interview examples

Case interview workbook (by Accenture)
Accenture case interview guide (by IGotAnOffer)

6. OC&C case interview examples

Leisure Club case example (by OC&C)
Imported Spirits case example (by OC&C)

7. Oliver Wyman case interview examples

Wumbleworld case sample (Oliver Wyman website)
Aqualine case sample (Oliver Wyman website)
Oliver Wyman case interview guide (by IGotAnOffer)

8. A.T. Kearney case interview examples

Promotion planning case question (A.T. Kearney website)
Consulting case book and examples (by A.T. Kearney)
AT Kearney case interview guide (by IGotAnOffer)

9. Strategy& / PWC case interview examples

Presentation overview with sample questions (by Strategy& / PWC)
Strategy& / PWC case interview guide (by IGotAnOffer)

10. L.E.K. Consulting case interview examples

Case interview example video walkthrough (L.E.K. website)
Market sizing case example video walkthrough (L.E.K. website)

11. Roland Berger case interview examples

Transit oriented development case webinar part 1 (Roland Berger website)
Transit oriented development case webinar part 2 (Roland Berger website)
3D printed hip implants case webinar part 1 (Roland Berger website)
3D printed hip implants case webinar part 2 (Roland Berger website)
Roland Berger case interview guide (by IGotAnOffer)

12. Capital One case interview examples

Case interview example video walkthrough (Capital One website)
Capital One case interview guide (by IGotAnOffer)

12. EY Parthenon case interview examples

Candidate-led case example with feedback (by IGotAnOffer)

14. Consulting clubs case interview examples

Berkeley case book (2006)
Columbia case book (2006)
Darden case book (2012)
Darden case book (2018)
Duke case book (2010)
Duke case book (2014)
ESADE case book (2011)
Goizueta case book (2006)
Illinois case book (2015)
LBS case book (2006)
MIT case book (2001)
Notre Dame case book (2017)
Ross case book (2010)
Wharton case book (2010)

5. How to practise case interviews

We've coached more than 15,000 people for interviews since 2018. There are essentially three activities you can do to practice case interviews. Here’s what we've learned about each of them.

5.1 Practise by yourself

Learning by yourself is an essential first step. We recommend you make full use of the free prep resources on our consulting blog and also watch some mock case interviews on our YouTube channel . That way you can see what an excellent answer looks like.

Once you’re in command of the subject matter, you’ll want to practice answering cases. But by yourself, you can’t simulate thinking on your feet or the pressure of performing in front of a stranger. Plus, there are no unexpected follow-up questions and no feedback.

That’s why many candidates try to practice with friends or peers.

5.2 Practise with peers

If you have friends or peers who can do mock interviews with you, that's an option worth trying. It’s free, but be warned, you may come up against the following problems:

It’s hard to know if the feedback you get is accurate
They’re unlikely to have insider knowledge of interviews at your target company
On peer platforms, people often waste your time by not showing up

For those reasons, many candidates skip peer mock interviews and go straight to mock interviews with an expert.

5.3 Practise with experienced MBB interviewers

In our experience, practising real interviews with experts who can give you company-specific feedback makes a huge difference.

Find a consulting interview coach so you can:

Test yourself under real interview conditions
Get accurate feedback from a real expert
Build your confidence
Get company-specific insights
Learn how to tell the right stories, better.
Save time by focusing your preparation

Landing a job at a top consulting company often results in a $50,000 per year or more increase in total compensation. In our experience, three or four coaching sessions worth ~$500 will make a significant difference in your ability to land the job. That’s an ROI of 100x!

Click here to book case interview coaching with experienced MBB interviewers.

35 Case Interviews Examples from MBB / Big Four Firms

Studying case interview examples is one of the first steps in preparing for the management consulting recruitment process. If you don’t want to spend hours searching the web, this article presents a comprehensive and convenient list for you – with 35 example cases, 16 case books, along with a case video accompanied by detailed feedback on tips and techniques.

A clear understanding of “what is a case interview” is essential for effective use of these examples. I suggest reading our Case Interview 101 guide, if you haven’t done so.

McKinsey case interview examples

Mckinsey practice cases.

Diconsa Case
Electro-Light Case
GlobaPharm Case
National Education Case

What should I know about McKinsey Case interviews?

At McKinsey, case interviews often follow the interviewer-led format , where the interviewer asks you multiple questions for you to answer with short pitches.

How do you nail these cases? Since the questions can be grouped into predictable types, an efficient approach is to master each question type. However, do that after you’ve mastered the case interview fundamentals!

For a detailed guide on interviewer-led cases, check out our article on McKinsey Case Interview .

BCG & Bain case interview examples

Bcg practice cases.

BCG – Written Case – Chateau Boomerang

Bain practice cases

Bain – Coffee Shop Co.
Bain – Fashion Co.
Bain – Mock Interview – Associate Consultant
Bain – Mock Interview – Consultant

What should I know about BCG & Bain case interviews?

Unlike McKinsey, BCG and Bain case interviews typically follow the candidate-led format – which is the opposite of interviewer-led, with the candidate driving the case progress by actively breaking down problems in their own way.

The key to acing candidate-led cases is to master the case interview fundamental concepts as well as the frameworks.

Some BCG and Bain offices also utilize written case interviews – you have to go through a pile of data slides, select the most relevant ones to answer a set of interviewer questions, then deliver those answers in a presentation.

For a detailed guide on candidate-led cases, check out our article on BCG & Bain Case Interview .

Deloitte case interview examples

Deloitte practice cases.

Undergrad Cases

Human Capital – Technology Institute
Human Capital – Agency V
Strategy – Federal Benefits Provider
Strategy – Extreme Athletes
Technology – Green Apron
Technology – Big Bucks Bank
Technology – Top Engine
Technology – Finance Agency

Advanced Cases

Human Capital – Civil Cargo Bureau
Human Capital – Capital Airlines
Strategy – Club Co
Strategy – Health Agency
Technology – Waste Management
Technology – Bank of Zurich
Technology – Galaxy Fitness

What should I know about Deloitte case interviews?

Case interviews at Deloitte also lean towards the candidate-led format like BCG and Bain.

The Deloitte consultant recruitment process also features group case interviews , which not only test analytical skills but also place a great deal on interpersonal handling.

Accenture case interview examples

Accenture divides its cases into three types with very cool-sounding names.

Sorted in descending order of popularity, they are:

These are similar to candidate-led cases at Bain and BCG. albeit shorter – the key is to develop a suitable framework and ask the right questions to extract data from the interviewer.

These are similar to the market-sizing and guesstimate questions asked in interviewer-led cases – demonstrate your calculations in structured, clear-cut, logical steps and you’ll nail the case.

These cases have you sort through a deluge of data to draw solutions; however, this type of case is rare.

Capital One case interview examples

Capital One is the odd one on this list – it is a bank-holding company. Nonetheless, this being one of the biggest banks in America, it’s interesting to see how its cases differ from the consulting ones.

Having gone through Capital One’s guide to its cases, I can’t help but notice the less-MECE structure of the sample answers. Additionally, there seems to be a greater focus on the numbers.

Nonetheless, having a solid knowledge of the basics of case interviews will not hurt you – if anything, your presentation will be much more in-depth, comprehensive, and understandable!

See Capital One Business Analyst Case Interview for an example case and answers.

Other firms case interview examples

Besides the leading ones, we have some examples from other major consulting firms as well.

Oliver Wyman – Wumbleworld
Oliver Wyman – Aqualine
LEK – Cinema
LEK – Market Sizing
Kearney – Promotional Planning
OC&C – Imported Spirits
OC&C – Leisure Clubs

Consulting clubs case books

In addition to official cases, here are a few case books you can use as learning materials.

Do keep in mind: don’t base your study on frameworks and individual case types, but master the fundamentals so you can tackle any kind of case.

Wharton Consulting Club Case Book
Tuck Consulting Club Case Book
MIT Sloan Consulting Club Case Book
LBS Consulting Club Case Book
Kellogg Consulting Club Case Book
INSEAD Consulting Club Case Book
Harvard Consulting Club Case Book
ESADE Consulting Club Case Book
Darden Consulting Club Case Book
Berkeley Consulting Club Case Book
Notre-Dame Consulting Club Case Book
Illinois Consulting Club Case Book
Columbia Consulting Club Case Book
Duke Consulting Club Case Book
Ross Consulting Club Case Book
Kearney Case Book

Case interview example – Case video

The limitation of most official case interview examples is that they are either too short and vague, or in text format, or both.

To solve that problem for you, we’ve extracted a 30-minute-long, feedback-rich case sample from our Case Interview End-to-End Secrets Program .

This is a candidate-led, profitability case on an internet music broadcasting company called Pandora.

In 30 minutes, this candidate demonstrates the exact kind of shortcoming that most candidates suffer during real case interviews – they come in with sharp business senses, then hurt their own chances with inadequate techniques.

Here are seven notable areas where the candidate (and you) can improve:

Thanking Throughout the case, as especially in the opening, he should have shown more appreciation for the time the interviewer spent with him.

Structured opening The candidate’s opening of the case feels unstructured. He could have improved it by not mixing the playback and clarification parts. You can learn to nail the case in a 3-minute start through this video on How to Open Any Case Perfectly .

Explicitness A lot of the candidate’s thought process remains in his head; in a case interview, it’s better to be as explicit as possible – draw your issue tree out and point to it as you speak; state your hypothesis when you move into a branch; when you receive data, acknowledge it out loud.

Avoiding silence The silence in his case performance is too long, including his timeout and various gaps in his speech; either ask for timeout (and keep it as short as possible) or think out loud to fill those gaps.

Proactivity The candidate relies too much on the interviewer (e.g: asking for data when it can easily be calculated); you don’t want to appear lazy before your interviewer, so avoid this.

Avoiding repeating mistakes Making one mistake twice is a big no-no in consulting interviews; one key part of the consulting skill set is the ability to learn, and repeating your mistakes (especially if the interviewer has pointed it out) makes you look like someone who doesn’t learn.

Note-taking Given the mistakes this candidate makes, he’s probably not taking his notes well. I can show you how to get it right if you watch this video on Case Interview Note-Taking .

Nonetheless, there are three good points you can learn from the candidate:

The candidate sums up what he’s covered and announces his upcoming approach at the start and at key points in the case – this is a very good habit that gives you a sense of direction and shows that you’re an organized person.

The candidate performs a “reality check” on whether his actions match the issue tree; in a case interview it’s easy to lose track of what you’re doing, so remember to do this every once in a while.

The candidate prompts the interviewer to give out more data than he asked for; if anything, this actually matches a habit of real consultants, and if you’re lucky, your interviewer may actually give out important pieces you haven’t thought of.

These are only part of the “ninja tips” taught In our Case Interview E2E Secrets Program – besides the math and business intuition for long-term development, a key feature is the instant-result tips and techniques for case interviews.

Once you’ve mastered them, you can nail any case they throw at you!

For more “quality” practice, let’s have a mock case interview with former consultants from McKinsey, BCG, Bain, Oliver Wyman, Strategy& and many other consulting firms. They will help you identify your problem areas and give you actionable feedback, making your preparation much easier and faster.

Hi! This is Kim and welcome to another performance in the Tips & Techniques part of our amazing End-to-end program. You are about to hear a really interesting performance.

There is a common Myth that Profitability cases are easier. Well, for beginners, that’s may make sense, but I would argue that Profitability cases can be really tricky and candidates without good foundation will make about the same level of mistakes regardless of type of cases given.

The profitability case we are about to watch will show that. It’s a very unconventional

Profitability. It started out like a typical one but getting more and more tricky toward the end.

The candidate is fairly good in term of business intuition, but the Tips & Techniques aspect needs a lot of fine tune! Now let’s go ahead and get started!

It’s actually a little better to playback the case information and ask clarifications. The candidate does not distinguish between the two and do both at a same time. Also, the candidate was asking these clarifications in an unorganized and unstructured fashion. This is not something terrible, but could have been better, especially when this is the very first part of the case, where the crucial first impression is being formed.

My pitch would sound like this:

“That’s a very interesting problem and I am happy to get the chance to solve it. First of all let me tell you my understanding of the case context and key objectives. Then I would like to ask a few clarifying questions regarding a few terminology and concepts. Both of these are to make sure that I will be solving the right problem.

So here is my understanding of the case: The client is ABC. Here are some DEF facts about the situation we just talked about. And the key case question is XYZ.

Does that correctly and adequately summarize the case?”

Once the interviewer confirms, I would move to the clarification part as follows: “Now I would like to ask a few clarification questions. There are three of them: No 1, … No 2, … and No 3, …”

You may see above pitch as obvious but that’s a perfect example of how you should open any cases. Every details matters. We will point out those details in just a second. But before we do that, it’s actually very helpful if you can go back, listen carefully to the above pitch, and try to point out the great components yourselves. Only after that, go back to this point and learn it all together.

Alright, let’s break down the perfect opening.

First of all, you hear me say: “That’s a very interesting problem and I am happy to get a chance to solve it”. This seems trivial but very beneficial in multiple ways:

1. I bought myself a couple of seconds to calm down and get focused. 2. By nature, we as human unconsciously like those who give us compliments. Nothing better than opening the case with a modest compliment to the interviewer.

And (c) I showed my great attitude towards the case, which the interviewer would assume is the same for real future consulting business problems.

You should do that in your interviews too. Say it and accompany it with the best smile you can give. It shows that you are not afraid of any problems. In fact, you love them and you are always ready for them.

Secondly, I did what I refer to as the “map habit”, which is to always say what you are about to do and then do it. Just like somebody in the car showing the drivers the route before cruising on the road. The driver would love it. This is where I said: “Let me tell you my understanding of the case context and key objectives. Then ABC…”.

Third, right at the beginning of the case, I try to be crystal clear and easy to follow. I don’t let the interviewer confused between playing the case vs. asking clarification questions. I distinguish between the two really carefully. This habit probably doesn’t change the outcome of how the case goes that much, but it certainly significantly changes the impression the interviewer has of me.

Fourth, in playing back the case, each person would have a different way to re-phrase. But there are three buckets to always include:

1. Who is the client 2. The facts regarding the client and the situation and (c) The key question and the objective of the case.

Fifth, after playing the case context and objectives, I pause for a second and ALIGN with the interviewer: “Does it correctly and adequately summarize the case?”. This is a habit that every consulting manager loves for young consultants to do. Nobody wants first-year folks to spend weeks of passion and hard-work building an excel model that the team can’t use. This habit is extensively taught at McKinsey, Bain and BCG, so therefore interviewers would love somebody that exhibits this habit often in case interview.

Lastly, when asking clarification questions, you hear me number them very carefully to create the strong impression that I am very organized and structured. I said I have three clarifying questions. Then I number them as I go through each. No.1, No.2, and No.3.

Sometimes, during interviews it’s hard to know exactly how many items you are going to get. One way is to take timeout often to carefully plan your pitch. If this is not possible in certain situations, you may skip telling how many items you have; but you should definitely still number your question: No.1, No.2; and so on.

Just a moment ago, the candidate actually exhibited a good habit. After going through his clarification questions, the candidate ended by asking the “is there anything else” question. In this case, I actually give out an important piece of data.

Though this is not very common as not every interviewer is that generous in giving out data. But this is a habit management consultants have to have every day when talking to experts, clients, or key stakeholders. The key is to get the most data and insights out of every interview and this is the type of open-ended question every consultant asks several times a day.

To show of this habit in a case interview is very good!

There are three things I would like you to pay attention to:

First, it took the candidate up to 72 seconds to “gather his thoughts”. This is a little too long in a case interview. I intentionally leave the 72 seconds of silence in the recording so you get an idea of how long that is in real situations. But it’s worth-noting here is not only that. While in some very complicated and weird cases, it’s ok to take that long to really think and gather ideas. In this case, the approach as proposed by the candidate is very simple. For this very approach, I think no more than 15 to 20 seconds should be used.

No.2, with that said, I have told I really like the fact that this candidate exhibits the “map” habit. Before going straight to the approach he draws the overall approach first.

No.3. You also see here that the candidate tried to align the approach with me by asking my thoughts on it. As I just said on the previous comment, this is a great habit to have. Not only does it help reduce chance of going into the wrong direction in case interviews, but it also creates a good impression. Consulting interviewers love people doing it often!

Here we see a not-really-bad response that for sure could be much better. The candidate was going into the first branch of the analysis which is Revenue. I would fix this in 3 aspects:

First, even though we just talked about the overall approach, it’s still better to briefly set up the issue tree first then clearly note that you are going into one branch.

Second, this is not a must, but I always try to make my hypothesis as explicitly clear as possible. Here the candidate just implicitly made a hypothesis that the problem is on the revenue side. The best way to show our hypothesis-driven mindset is to explicitly say it.

Third, you hear this a ton of times in our End-to-End program but I am going to repeat it again and again. It is better to show the habit of aligning here too. Don’t just go into revenue, before doing that, give the interviewer a chance to agree or to actually guide you to Cost.

So, summarizing the above insights, my pitch would sound something like this:

“So as we just discussed, a profit problem is either caused by revenue or by cost. Unless you would like to go into cost first, let’s hypothesize that the problem is on revenue side. I would like to look deeper into Revenue. Do we have any data on the revenue?”

And while saying this, you should literally draw an issue tree and point to each as you speak.

There is an interesting case interview tip I want to point out here. Notice how the candidate responds after receiving two data points from me. He went straight into the next question without at least acknowledging the data received and also without briefly analyzing it.

I am glad that the candidate makes this mistakes… well, not glad for him but for the greater audience of this program. I would like to introduce to you the perfect habit of what you should react and do every time you have any piece of data during case interviews. So three things you need to do:

Step 1: Say … that’s an interesting piece of data. This helps the interviewer acknowledge that you have received and understand the data. This also buys you a little time. And furthermore, it’s always a good thing to give out modest compliments to the interviewer.

Step 2: Describe the data, how it looks, is there any special noteworthy trend? In this case, we should point out that revenue actually grew by more than 50%.

Also notice here that I immediately quantified the difference in specific quantitative measurement (in this case, percentage). Saying revenue went up is good, but it’s great to be able to say revenue went up by more than 50%.

Step 3: Link the trend identified back to the original case question and the hypothesis you have. Does it prove, disprove, or open up new investigation to really test the hypothesis? In this case, this data piece actually opened up new investigating areas to test the hypothesis that the bottleneck is within revenue.

My sample pitch for this step 3 would sound like this: “It’s interesting that revenue went up quite a bit. However, to be able to fully reject our hypothesis on the revenue, I would like to compare our revenue to that of the competitors as well.”

Then only at this point, after going through 3 steps above, I ask for the competitors’ revenue like the candidate did.

Notice here that I ended up asking the same question the candidate did. This shows that the candidate does have a good intuition and thought process. It’s just that he did all of these implicitly on his head.

In consulting case interview, it’s always good to do everything as explicitly as possible. Not only is it easier to follow but it helps show your great thought process.

… the rest of the transcript is available in our End To End Case Interview

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Scoring in the McKinsey PSG/Digital Assessment

The scoring mechanism in the McKinsey Digital Assessment

Case Interview End-to-End Secrets Program

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Case interview in consulting is difficult with the passing rate is around 10%. This is because big consulting firms keep an extremely high recruitment standard

A case interview is where candidates is asked to solve a business problem. They are used by consulting firms to evaluate problem-solving skill & soft skills