10 Tips for Acing Your Consulting Case Interview,

Competition for consulting jobs can be fierce, so firms rely on case interviews to distinguish between candidates. Interview processes at prestigious consulting firms tend to include numerous cases involving a variety of industries which are posed by interviewers at different seniority levels, from Associate to Partner.

Case interviews are centred around a high-level business problem such as profitability or market expansion, requiring candidates to demonstrate numerical, analytical and communication skills. They are known to be difficult as you’re faced with a brand new industry and scenario every time so you can’t simply memorise and regurgitate a load of information to the interviewer.

Here are some tips on how to prepare and ace your next consulting case interview:

1. Why Are You Here?

Prior to the interview, have a good think about why you want to enter the world of consulting, particularly the firm at which you’re applying. The interviewer will almost definitely pose this question before starting the case study exercise, so be sure to have a few strong reasons backed up by previous experiences.

2. Fast Hands

At the start of the case, the interviewer will provide the background to the business problem you’ll be exploring, so be ready to keep up with the interviewer and note down key facts such as:

• Client and/or ‘target’ (if M&A)
• Business model
• Problem statement
• Objective & Success metric
• Geography
• Timescale

3. Remember To Clarify!

Once the background information has been provided by the interviewer, you should run through all of it and then clarify any areas you’re unsure of, particularly items from the list above. This shows that you’re thinking about the problem at a deeper level and want to avoid making false assumptions. Try to make the questions as pertinent and focused as possible but never be afraid to ‘over-clarify’ in order to deliver a stronger response. There is no such thing as a silly question.

For example, you might ask:

• What is the primary success metric?
• What is the timeframe for achieving the objective/success metric?
• Which markets is the business focused on?

4. Becoming An Architect

There are numerous generic frameworks scattered across the web which help with tackling the majority of case studies. However, the best candidates tend to opt for a bespoke structure that is most suited to the particular context and problem.

Let’s say the case study is about a mattress company who are keen to boost their profits over the next 2–3 years. A generic framework would entail splitting profit into revenue & cost, revenue into price & volume, cost into fixed & variable and then providing some initiatives that would help increase price/volume and decrease fixed/variable costs. A better approach would be to first break down revenue into specific streams and business models that a mattress company would typically utilise (e.g. households vs. hospitals vs. hotels, B2B vs B2C vs D2C) and then think about targeted opportunities to increase price/volume and decrease fixed/variable costs. This kind of structuring can also help with the market sizing exercise during the interview.

5. ‘Guesstimation’ Time

Prior to the interview, spend some time looking through key market/geographical stats and figures. These will prove useful in the market sizing section of your interview where you may be required to estimate the size of the basketball market in the UK as an example.

Some examples of key stats and figures that could help:

Population

• World: 8 billion
• China: 1.5 billion
• India: 1.4 billion
• Europe: 750 million
• US: 300 million
• Japan: 125 million
• UK: 70 million

GDP

• US: $21 trillion
• China: $15 trillion
• Japan: $5 trillion
• Germany: $4 trillion
• UK: $3 trillion

Market Sizes

• Car & Automobile: $4 trillion
• Footwear: $300 billion
• Food & Grocery: $12 trillion
• Apparel: $1.5 trillion
• Hotel & Resorts: $1 trillion
• Tourism: $1 trillion
• Average persons per household: 3 people
• Average life expectancy: 80 years
• Population Distribution: equal split (~25% each) between 0–20, 20–40, 40–60 & 60+

6. Numerical Ninja

Throughout the interview, you will have to analyse data and carry out some basic numerical calculations. It is important to train your mental agility prior to the interview so you can blaze through the number-crunching with accuracy and ease. Remember, you don’t need to get the mental calculations 100% accurate, just rough order of magnitude. For example, if you needed to calculate 49 × 30, you can instead calculate 50 × 30 = 1500 which is completely fine in the interview.

Have a go at these calculations and see if you can answer all of them in under a minute!

1. Multiply 181 by 98
2. What is 39% of 85 million?
3. What is 18500–3849?
4. What is 95 million + 49 million?
5. What is the compound interest for 5 years on £50k at 20% per annum?

7. Audible Thoughts

Remember to verbalise your thought processes out loud so the interviewer understands how you’re approaching and breaking down the problem. Sometimes they may offer you a helpful tip to point you in the right direction — make sure you heed this advice immediately and explain how you are correcting your approach or thinking.

8. Does It Make Sense?

Sense check everything. Literally everything. Most of the case study will involve you thinking of creative solutions on the spot backed by numerous assumptions. Whenever you arrive at a number after a market sizing exercise or near the end of the case study, make sure to ask yourself whether the order of magnitude seems reasonable.

9. Step Back

Whenever you arrive at a solution or proposition, always evaluate your approach. Acknowledge and scrutinise the assumptions you have made by sharing your confidence level and the impact that has on the final answer. The interviewer wants to be reassured that you’re aware of the weaker assumptions and whether the final solution would still hold if the ‘true’ figures were higher or lower.

10. Question To Impress

After the case study has finished, the interviewer will allow you to ask some questions. Asking thought-provoking questions will show them you’ve researched the firm and industry and are keen to dig deeper and learn more. You should avoid generic questions such as “How many people work in the company?” or “What is the salary for this role?” and instead focus your efforts on getting a candid perspective on the culture and projects of the firm from the interviewer.

In Summary

Consulting Case interviews can be tricky. Make sure you spend a good amount of time familiarising yourself with the interview structure and honing your note-taking and mental maths. Try to find a partner to practice interviewing with so you can improve your communication skills and iron out any bad habits. Most importantly, run through as many cases as you can to expose yourself to new scenarios and problems. And most importantly, good luck with your interview!