Cheapest/most efficient way to prepare for MBB interviews?

Case Interview Prep First Time Case Interview! Help Appreciated! MBB case interview prep
New answer on May 11, 2020
10 Answers
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Anonymous A asked on May 11, 2020

Hi all,

First time poster here. I'm a life science PhD grad looking at moving into consulting and will be applying to MBB firms. I'm a novice in the industry starting from scratch and I've been quite overwhelmed at the amount of resources to prep for interviews etc. and was hoping to ask people who have had experience to help me narrow the focus! In addition, upon looking at some of the prices of these prep courses I just want to make sure that I spend my money on the right courses so I don't spend money into books/online courses that aren't actually useful.

Any help or info would be very greatly appreciated!

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Content Creator
replied on May 11, 2020
#1 Coach for Sessions (4.000+) | 1.500+ 5-Star Reviews | Proven Success (➡ | Ex BCG | 9Y+ Coaching

Hi there,

I would recommend the following steps to organize your preparation:

  1. Define a calendar for your preparation. Check if there is any deadline for the applications. Then identify how many hours you have before that and allocate a time slot for preparation in your calendar for each day, working on the points below. Many people need 100+ hours to be ready before the interview so you can keep that as a benchmark
  2. Read Case In Point or Case Interview Secrets for a general understanding of what a consulting interview is. Don’t focus on the structures proposed in the books though, as they are not good enough nowadays.
  3. Start reading good MBA Consulting Handbooks – you can find several for free online (Insead is a good one to start). Read the cases and try to apply your structure to solve them. Whenever you see there is something missing, upgrade your structure with the new insides. PrepLounge also has a Case Library that you can use. Try to read at least a new case per day – in this way you will absorb better the information with constant learning.
  4. After the first 5-10 cases in books/handbooks and basic theory, start to practice live. PrepLounge can be helpful to connect with other candidates for that. There is a relevant part of the interview score that is based on your communication, which you cannot practice at all if you read cases only. Keep track of your mistakes and see if you repeat them. If so, try to identify the source of the mistake (feedback of experienced partners would be particularly useful for this). Be sure to focus on both the behavioural part and the case part. The case part should also cover market sizing, mental math and graph analysis.
  5. Before your application, be sure to review your CV and Cover, so that they are in the required format for a consulting application
  6. At least three weeks before the application deadline, start networking to find referrals for your target companies. You can find some tips on how to do that here:
  7. Once you feel you are not improving anymore, if you have a tight time constraint or if you want a realistic assessment of your level, consider using support from experts to strengthen your performance
  8. Before the interview, be sure to prepare your questions for the interviewer –great way to show you prepared in advance and to connect with the interviewer for a good final impression.



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Anonymous replied on May 11, 2020

Hi There,

I think the other coaches have covered a lot of tips for you! If I had to add my two-cents on the topic, here is my recommendation:

1) Start with Victor Cheng's website and youtube videos. He is very well-paced and provide a nice initial toolkit to start getting comfortable with cases.

2) Most probably, your school might have a "consulting club" where students get together and practice cases - a case partner is very important (because reading a case is very different than actually solving it)

3) Reach out to the LoungePrep community, here you can find a lot other potential applicants looking for partners

4) Once you know your case solving ABCs, reach out to a coach - coaches on prep lounge can give you the extra boost that you need to increase your chances of acing the interview. Most of them were actual interviewers, so they can give you a nice simulation and insightful feedback to bring out your full potential.

Best of luck in the process, feel free to reach out for any additional tips.



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Anonymous replied on May 11, 2020

Hi there,

It doesn't have to be expensive to prepare for MBB interviews. You just need to be a bit resourceful.

1) Starting point: I suggest you read Victor Cheng's book "Case Interview Secrets". It is only around 20 dollars and it is very comprehensive and easy to understand.

2) Math: Given you are a life science PhD, I think you should be quite good with numbers? You can also practice using some GMAT math materials (there are a lot free ones online).

3) Case prep: Leverage your friends or peers on PrepLounge to have free practices. Once in a while, consider using a coach to get systematic feedback and tips, then go back to your free practice before you check in with a coach again. You only need a few sessions with coaches, it won't end up a big sum.

4) CV/Fit question: A lot of the work here can be done by yourself, without the need to spend a lot. If you want to make sure, just 1-2 sessions with a coach to go through and help you brush up would be enough.

There are a lot of materials here on PrepLounge (including our answers in Q&As), which you can leverage for free.



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Content Creator
replied on May 11, 2020
MBB | 100% personal interview success rate (8/8) and 95% candidate success rate | Personalized interview prep

Hi there!

First, good luck!

Second, the most important thing here is narrowing down the noise. There is a lot of content flying around, and you need to work hard to focus on what's important (much like when solving a case).

I recommend the following:

1) An initial planning session with a coach: 1 hour with a coach now will have a productivity multiplier effect on all your efforts moving forward. They will figure out what materials are best for you, guide you towards the best ways to learn, and come up with a preparation plan with you.

2) Leverage free resources first: PrepLounge Q&A and case library, Poets and Quants, SpencerTom, Google, etc.). Leverage these options, read-up, and over time you'll get a feel for what you really need and where you really need to invest your hard-earned $

3) Case with other PrepLoungers: Casing with other PrepLoungers is free. Not only do you get to practice casing, but you get direct feedback. Additionally, you learn a lot just from casing others. Finally, from other PrepLoungers you'll learn which materials/coaches are helpful.

In summary, while free options don't beat paid options, you can use them for a while to get a feel for what works for you. Have an initial coaching session to get you on the right track, then go the paid route when it's clear either 1) You are stuck or 2) It's clear the paid route will improve your productivity/progress

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Content Creator
replied on May 11, 2020
McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School


I recommend the following approach:

1) Start with "Case in point" book - you can download this book for free everywhere. It's not the best guide on how you should approach the cases, however, it will give you the basic understanding.

2) Start practicing cases with partners here or find them locally. !!! Find experienced partners or coaches who can provide a good feedback!!!

3) Purchase and read Viktor Cheng Book (Amazon Kindle store) and listen to LOMS (his website). I recommend to reread the book and listen to LOMS every 15 cases. Every time, having more experience, you’ll be finding something new.

4) Practice fast math

  • Learn how to multiply double digit numbers (
  • Learn the division table up to 1/11 (i.e. 5/6 = 83.3)
  • Learn how to work with zeros (Hint: 4000000 = 4*10ˆ6)
  • Use math tools (Mimir math for iOS), Math tool on Viktor Cheng website to practice

5) Below you can find a list of the most common case types and some high-level recommendations on structuring:

  • Market sizing - structuring from the supply or demand side. Structuring using a formula or using an issue tree
  • Profitability - basic profitability framework. Remember about different revenue streams and product mix
  • Market context cases (Market Entry, New product, Acquisition, etc). Always start with the big picture "market". Finish with something specific to the case (e.g. How to enter?"). Structure it as if you are defining the work streams for the real project.
  • Operational math problem (e.g. Should we increase the speed of an elevator or just buy a second one? How should we reduce the queues? Etc.) - Structuring as a process / value chain, with inflows, operations, and outflows
  • Cost cutting - I provided the recommendations on structuring it here:
  • Valuation - Purely financial structure with cash flows, growth rate, WACC / hurdle rate, etc.
  • Synergies - revenue synergies (price, qty, mix) and cost synergies (value chain).
  • Social / economics cases (e.g. How to improve the quality of life in the city? How to increase the revenues of the museum?) - huge variability. Practice 3-5 social cases before the interview

6) Also, I would try to focus on the most common industries in the following priority(sorted by probability of getting a case): 1-retail and CPG; 2-airlines; 3-Telecom; 4-banking; 5-natural resources; 6-tech

7) ! Important: don't forget about the FIT interview part. Crafting you stories and backups stories will require a couple of weeks!


Here is a good list of articles regarding the different parts of the case:

1) Start with clarifying questions:

2) Communicating while structuring. Here is a long post by me on how to communicate the structure during the case study:

3) Using hypotheses. I made a post about hypotheses here:

4) Communicating while making calculations:

  • Always tell the interviewer your approach
  • Check with the interviewer that your approach is correct
  • Come to the interviewer with some preliminary answers
  • Check your assumptions with the interviewer

5) Communicating during the analysis of graphs / tables

  • Take a minute to look at the graph. Read the graph title. Look at the graph type and define the type (pie chart, line chart, etc). Look at the legend (ask for clarifying questions if necessary). Identify whats going on on the graph. Look for: Trends, % structures. Look for unusual things - correlations, outliers,
  • Make 3-4 conclusions from the graph. Think out loud on potential hypothesis on what could be the root cause / what are the consequences
  • Prioritize the most important for your current analysis and move forward with the case

6) Communicating while having questions on creativity

  • Ask an interview for a minute to think
  • Think of several buckets of ideas (e.g. organic growth / non-organic growth / differentiation). Remember to think as big as possible
  • Narrow down to each bucket and generate as many ideas as possible
  • Present the structure (buckets) and then your ideas

7) Communicating your conclusion. You can find a good example I've posted here:

8) Communicating your FIT stories

Use the top-down approach while communicating your stories. "The Pyramid Principle" is the must-read by ex McKinsey on this topic.

I recommend using the STAR framework:

  • In Situation, you should briefly provide the context, usually in 1 or 2 sentences
  • Task usually includes 2 or 3 sentences describing the problem and your objective.
  • Then you provide a list of specific actions you took to achieve the goal. It should take 1 or 2 sentences per action (Usually 3-4 actions). Note that the interviewer can stop you any minute and ask for more details.
  • The results part should have 1 or 2 sentences describing the outcomes. This part is finalizing your story - make sure it can impress the interviewer and stay in the memory.


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Content Creator
replied on May 11, 2020
McKinsey | MBA professor for consulting interviews

there are 4 aspects of the application process you have to focus on:

  • CV and cover letter: prepare impactful documents that highlight your achievements, skills, and motivation.
  • Test: you should understand if your office assesses candidates with PST, SHL or Imbellus, since every McK office can use one of these 3 standards.
  • Personal Experience Interview: fit and CV questions to assess your personal impact, leadership skills, and entrepreneurial spirit. You should prepare impactful stories about your experiences that cover these 3 main pillars.
  • Case Interview: typical business case to evaluate your structure in approaching problems, problem-solving skills, and business sense. This is the most time-demanding aspect to work on. I recommend reading Cosentino's Case in point to fix the theory. Then, what will be really important is practicing mock cases with other candidates here on Preplounge.

Hope it helps,

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Content Creator
replied on May 11, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut


Agree with you, the amount of info is overwhelming.

To add to the other comments, and if you wnt to have the info consolidated and don´t jump from one source to another when it comes to FIT, I recommend you the FIT guide that hs been just published in PrepL.

PM if you are interested for disccount codes.

Hope it helps!



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Anonymous replied on May 11, 2020

Dear A,

I would recommend you the following algorithm:

1. Identify the companies interesting for you. Many people are interested mainly in MBB, you can start defining the exact list of companies interesting for you for the internship
2. Check the requirements and application details.
3. Start your preparation with reading Case In Point by Cosentino for a general understanding of what a consulting interview is.
4. Start learning and practicing the cases. Some you can find in Case Library and practice it with your partner or experience coach.
5. Purchase and read Viktor Cheng Book (Amazon Kindle store) and listen to LOMS

Once you feel you are not improving anymore, I would recommend you to take an expert coach for structured feedback and polishing your own performance.

Hope this helps,



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Amber replied on May 11, 2020


In this quarantine time I think you should choose an online prep course. I purchased E2E by mconsultingprep last 2 months and practiced it all day since the lockdown. To me it is just so great and super effective even for a non-business background like me. The case interview simulation video were very easy to understand and insightful. Their teaching method is ok enough to me, structured and transparent.

They gave me a 30% discount code. it makes the courses cheaper than other online courses. Here: mcphpctm3. hope it help!


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Alex on May 11, 2020

agree. way cheaper than online coaching and still effective

Content Creator
replied on May 11, 2020
150+ interviews | 6+ years experience | Bain, Kearney & Accenture | Exited startup| London Business School

I agree that it is good to stick to one source; there is a lot of good material out there (including study plans). If you are thinking of professional coaching too, I would recommend planning a few sessions with a coach to train specific advanced topics (vs doing the basics).

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Francesco gave the best answer


Content Creator
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