Acing the Case Interview (2022)
Case Interviews are central to the selection process of consulting firms such as McKinsey, Bain and BCG. Most recently, non-consulting firms such as FMCGs and Tech companies have been incorporating these interviews in their selection process for business-related roles as well.
The preparation and actual interviews may feel intimidating, but this is rarely the case! I hope that my experience of case interviewing (with decent success!) after doing more than 40 practices cases, 30 actual interviews, and getting numerous offers would be useful in getting you started :)
Overview
- Introduction. Structure, Interview Profiles, Success Rates
- Case Interview Preparation. How you can think about preparing for the interviews
- Within the Case Interview: Tips and Optimizations that I found useful for my interview
Introduction
Case interviews present you with a hypothetical scenario (usually business-related), in which you are expected to structure/identify the challenges and drive towards insights and recommendations. Firms are usually more interested in your thought process — getting to the right answer is less important here.
Take a look at McKinsey’s, Bain’s, and BCG’s case interview pages where they describe the process. Some commonalities: these interviews put you in the hot seat of solving real client challenges (albeit in a simulated environment) where you are to showcase your problem-solving skills (eg. how you approach, how you analyse the issue, identify critical information, and synthesis insights).
Watch this video for a sample case interview by CaseCoach:
That sounds like a lot, doesn’t it? But not to worry, let’s break it down below.
Structure
While the majority of case interviews are structured as above, you should be prepared for anything that the interviewer plans for. For example, I had encountered situations where there wasn’t a Fit/Q&A section, and where the actual case took only 10 minutes (it was a simple market sizing, and spent more time chit-chatting afterwards).
I will be focusing on the case portion of the interview in this article. There are plenty of resources covering the fit portion online :)
What to expect during the entire interview process?
Interview Stages & Timeline
Note: Interview timelines are office-specific and may differ across locations. Do check with your recruiters for the actual timelines. This guide is written for the South East Asia region.
Generally, there will be two stages of interviews (First Round & Final Round), with at least 2–3 cases per round. Firms (eg. OW) may conduct an interview super-day, where all of their cases are scheduled back to back in a single day(super draining!).
Results from the first round would usually take a week, while final round results may take a little more based on the number of internal discussions.
Interviewer Profiles
First Rounds will usually be conducted by Managers/Principals, while Final Rounds will be conducted by Partners/MDs.
Through my experience, I found that interviews conducted by junior folks will be relatively straightforward and normal. They would have prepared a case beforehand and would not deviate too far from the script. These cases tend to have some exhibits as well.
This is in contrast to Partners who have the ability to ask *anything* on their minds. Partner cases tend to have few exhibits (I only encountered 1 partner who had an exhibit) and are more on the qualitative side.
Success Rates
Consulting companies are notorious for being extremely selective and hard to get into. There are multiple screening processes that you have to pass just to land a first-round interview. These processes include basic resume screening, college grade criteria, and online interviews (see this article for more).
Generally, the pass rates will increase as you progress from stage to stage. From what I recall/estimate, you have to be around the top 10% of applicants to secure a first-round interview. Next, you need to be in the top 30% of first-round interviewees to be considered for the final round. Final round success rates can range from 20%-60%.
Case Interview Preparation
Case Interview prep may sound daunting at first, but with a clear strategy, you can achieve the mastery required to do well and succeed. I have broken up my practice experience below.
I had completed around 40+ practice cases (honestly, too much. Don’t do it!) and around 20+ actual cases. While there isn’t an ideal number for case preparation, I would advise against doing too many cases. I did not feel any marginal benefit from doing more cases after the 20-ish mark. What is the ideal number? Read on to find out.
Part 1: Gaining Context
Start by watching YouTube Videos: I began by understanding how cases worked by watching videos by Victor Cheng and demo-cases on YouTube. It should serve as a good primer for you. Try to follow along with each video case by pausing the video, writing your answers down, and then comparing it with what the interviewee did. As with anything on the internet, do watch each video with a pinch of salt, as some may be inaccurate or outdated. You can save your time by clicking on those I listed here.
Read the following articles here: These are some foundational articles that provide good information on the entire process. They also provide some initial frameworks for you to adopt.
Part 2: Finding your Case Partners and Practice
One of the biggest hurdles I faced was attempting my first mock case (It was a disaster btw). It is scary trying to solve these cases in front of your friends, doing live-math, and the fear of making so many mistakes… it does get to you. However, it is normal to struggle at the start! With more experience, you can definitely get better.
Practice Structuring/Frame-working on your own: You can look through the casebooks (linked here). For each case, read through the initial prompt and draw out your structure. Once done, compare it with the casebook answers to see how you could improve/done things differently. This can serve as a quick and efficient exercise to train your structuring skills for the real interview.
Casing with People: Grab a few of your friends who are joining the application cycle to practice with.
Don’t just be the interviewee, but be the interviewer as well. Many of my learnings were gained when taking on the role of the interviewer. This can give you a different POV which can provide different insights to you.
Establish a regular cadence (eg. Once per Week) and stick to it religiously. Try practising with different people as this can expose you to different styles of interviewing. Most importantly, ensure that your case partners are equally committed to casing and can give quality feedback.
Don’t know anyone who is casing? Reach out to your career services for help, or search Facebook for Case Practice Groups as there are tons of people looking to case as well.
Keep a Case Record: This helps you to track your progress as you practice. See the below for my structure, but feel free to create one that suits your needs.
Part 3: Be Targeted: Working on your Weaknesses
At this point, you would have done a significant number of cases already and have gotten into the groove of things. Your focus here should be practising specific case types, instead of the volume of cases.
Focus on case types that you struggle with: With your case record, you can identify areas that you are weak in. Ask your casing partner for cases that challenges your weaknesses so that you can improve further, as there is no point in repeating case types that you are comfortable with. Personally, I remember having a certain discomfort with market entry cases and had asked my case partners to focus on those until I felt more confident. This paid off immensely, as I had a significant amount of Market Entry cases during my first-round interviews.
Always internalise your mistakes: You will only benefit from more practice only if you internalise the mistakes and learnings. If not, you will just be going through the motion of case practice and your progress will plateau. Unsure if marketing is a fixed or variable cost? Figure it out before your next case. Unsure how to structure a profitability turnaround? Learn before your next case.
How to tell if you are ready? When your case partners start nit-picking about your performance. If “less-fundamental” feedback such as your tone, choice of words, and facial expressions come up instead of more integral factors such as structuring and communication, you should be relatively ready for the real thing.
Part 4: Cadence during your Interview Period
By this time, you should have completed at least 20+ practice case interviews, and have gained exposure across different case types (P&L, Mkt Entry, Operations, etc.). You are also comfortable in tackling any problem that gets thrown at you and are good at case math.
Light practice keep your mind sharp: Before each interview, I usually have a practice case 2/3 days before the actual interview just to keep my brain sharp. I would advise against practising right before your interview (to save some brain stamina) as case burnout is a real thing.
Reflect after Every Interview: Spend a few minutes reflecting on areas for improvement while the case is still fresh in your mind. The next interviewer would likely be testing you on areas that you could have performed better (yes, the interviewers share notes).
Do not over practise: Think about the law of diminishing returns. Case Interviews require your mind to be sharp and alert, so adequate rest is required. I would also advise against trying to understand all the industries out there — this is very time-consuming and inefficient. You won’t be expected to become a subject matter expert during the case and your interviewers will be more than willing to explain/clarify cases that are situated in less common industries.
Case Interview Tips
These tips are based on my experience interviewing/being interviewed by other people. I will be using a fictitious and super-simplified case to illustrate the tips and optimizations you can leverage to do well in your case interview.
Welcome to McBain Consulting Group (MCG). Our client, BreadNButter is a sandwich stand operator located in the Central Business District. He is exploring the idea of expanding to the nearby waterfront area. She asks you what to do.
Tips
- Do not just repeat the initial prompt verbatim, but be insightful as well.
Most candidates will repeat the prompt verbatim, and you won’t be remembered for your ability to take notes and capture information. Draw on your experience/knowledge of the industry/problem, and share some mini-hypothesis at the start of the case, or something that stands out to you based on the initial facts.
Example of starting the case: “This is interesting… I suspect that BreadNButter is facing some serious headwinds given the increase of Work From Home amidst the pandemic which results in lower revenues.”.
This illustrates to the interviewer that you are actively thinking (being hypothesis-first) about the case right at the start. Do not try to force the issue though. Not saying anything is better than trying to say something for the sake of saying it.
- Vocalize your thought process to your interviewer
Whether you are coming up with various insights or doing case math, remember to vocalize your thought process to your interviewer. This will enable them to follow you much easier (especially important given the online nature of case interviews now).
- When structuring, do not regurgitate the typical frameworks to solve the case.
Think of the standard frameworks as training wheels. Once you get the hang of cases, you have the ability to think and structure the problem by yourself. Relying on standard frameworks only allows you to solve straightforward “case-book” cases, and will not give you the edge to tackle cases of higher difficulty. Instead, make sure that your initial framework is purpose-built for the problem at hand. Approach the problem from first-principles and think about what factors/hypothesis is most central to the case.
For example, I got asked a question about how an apple tree farmer can commercialize his apple tree. There isn’t an out-of-the-box case framework that can address that instantly.
- Be structured in anything you say/do. Extremely Important!
Interviewers will be assessing your ability to structure complex and ambiguous issues. Always communicate top-down, and bucket your issues! This will allow the interviewer to grasp and follow your train of thought easier. Practice more cases to build up this mental muscle and make it a habit for you.
- For Video Interviews, draw out your structure on paper, and actively show the interviewer your paper.
Pre-COVID, interviews were conducted in person which allowed the interviewer to see your structure. This is an important step, as the interviewer has to give you the “green light” to proceed with your structure (if you have gone off tangent, they will help guide you back on the right track). Online interviews make it difficult for you do to so, and most candidates have just resorted to verbally going through their structure.
While it is okay to do so, showing your paper via the webcam to your interviewer is much more effective than just verbalizing it. You are harnessing the power of visuals to communicate effectively (just think of it as a PowerPoint slide!). Of course, you have to adjust this for each interviewer’s preference.
- Your initial structure/framework will is especially important. Don’t forget about it as you progress along with the case.
Use the structure as a map for navigating the case. Whenever you get stuck or have reached a dead-end after drilling deeper into one branch, always take a step back and evaluate your options using the initial framework that you created. This will demonstrate your ability to see the big-picture and not get too bogged down when solving a specific branch.
- Exhibit strong case leadership/initiative
Strong case performers are always thinking about what’s next (or in other terms, the “so what?”). Even when you are doing a deep dive within a single branch, always keep in mind the bigger picture and think about how you can proceed with the current information at hand. Show the interviewer your initiative by driving the case forward to derive insights.
Example of Case Initiative: “I have found that the market for the waterfront region is large, with around 10M sandwiches sold with a CAGR of 20% Y-oY. This is very attractive for BreadNButter. However, given the strong numbers, I would expect the competitive space to be heating up fast. I would like to examine the competitive environment within the waterfront region, so as to determine whether it is favourable for BreadNButter’s entry”
- Good Summarising: Ending the case by reporting to the CEO.
This is an often overlooked part of the case, given that candidates at this point would be mentally drained and want to get it over and done with. This causes mistakes that I commonly see: 1) Repeating whatever was discussed during the case 2) Bottom-up instead of top-down communication 3) Talking too long instead of sharing the most pertinent points. Just remember that less is more, be succinct as possible by sharing the most pertinent actionable information that the CEO needs to know.
Compare the conclusions below:
Conclusion #1: Hi CEO, thank you for this engagement. We believe that BreadNButter should enter the waterfront market for sandwiches based on the following reasons.
Firstly, the waterfront market opportunity is large with high demand and demand growth. Secondly, we can enjoy the first mover’s advantage due to the lack of competition and a fragmented market. Finally, we can leverage the economies of scale by increasing our sandwich production capacity.
If you are okay with proceeding, our team will spend the next week developing the market entry strategy for BreadNButter and will revert to you by the following week with our recommendations. Thank you.
Conclusion #2: Hi CEO, thank you for this engagement. To decide whether to enter the market for sandwiches, we first looked at the market size of each region. We found that waterfront region has the best market potential given the large number of consumers and the increasing demand trends for the product. This shows that the waterfront region is the best in terms of market size. After which, we conducted a robust competitor analysis in the region. To do this, we did a bottom-up estimation of your competitor’s market share, and found that the market is very fragmented, and the largest competitor only has a market share of around 10%. This means that it is easy to enter the market. Finally, we analysed the companies synergies and found that there are some synergies that we can leverage on, namely economies of scale with existing operations. Based on all of these three factors, your company should proceed with entering the waterfront region.
As you can see, conclusion #1 is way more succinct than conclusion #2 which is too convoluted and messy. Remember that these CEOs have limited time with you. Focus on the content and recommendations rather than the process of how you arrived at them.
- It is okay to ask for time to think!
You won’t be expected to know all the answers instantly. Be comfortable with asking for some time to think and process information. Interviewers are nice people and would always give you some moments to organise your thoughts and think (Of the 30+ interviews I went through, I have never encountered someone who denied me the time to think).
- Keep Calm, and don’t let nerves get the better of you
You will definitely meet a difficult interviewer, or face a case that you have no clue about during the process. As with anything, the most important thing you can do is to remain calm. Remember that you already have what it takes to succeed, so just take a step back and do not be flustered. Do not show your nerves to the interviewer.
In one of my interview rounds, I encountered a partner who wasn’t the most encouraging (kept saying NO to every idea I brainstormed, told me that my hypothesis was wrong, etc.). Thought I flunked it, but I made it through to the next round. The feedback was that I was calm and maintained my composure despite the difficult environment.
- Be memorable. Everyone can crack the case, so how can you stand out. Why are you memorable?
Everyone will achieve a certain level of case mastery after practising cases, and it will not be enough just to crack the case. This is especially so for final rounds where candidates are usually top-calibre.
You need to be memorable to your interviewer for them to put you through. Could your general knowledge make you stand out? Or is it your personality and ease of interacting with senior folks that makes you super likeable? Perhaps your analytical/quant power impresses people?
Find out what is your spike and make it shine in the interview.
- Be Kind, Be Helpful and Pay it Forward.
I have benefitted from the help of numerous friends and acquaintances during my application process. Interviewing for consulting is difficult, and I wouldn’t have been able to succeed without their guidance, support, and encouragement. The process can get extremely stressful at times, so be tactful (eg. don’t go around announcing your progress into the final round), be kind and helpful (help fellow applicants out, such as offering to case them), and pay it forward.
Final Thoughts
I hope this guide would help to de-mystify the entire consulting interview process and offer various tips that you can leverage for your own applications. If you found this helpful, please leave a clap/share this article with people who would find this beneficial!
One final thing: Regardless of whether you get the offer or not, remember that consulting is not the only job out there. Do not be overly fixated on getting a consulting offer. I’ve had friends who only optimized their resumes for consulting and had difficulty pivoting to other industries as they were unable to secure a consulting offer. Be willing to broaden your horizons as there are so many opportunities out there.
All the best!
