Ernst & Young (EY-Parthenon) case interview: the only post you'll need to read

Compared to a typical corporate interview, Interviewing at EY and their strategy subsidiary Parthenon, is very difficult. EY-Parthenon uses a combination of case interviews, behavioural interviews, and group case presentations to evaluate candidates.

If you're new to the case interview process, then this might sound overwhelming. But don't worry! We've helped over 30,000 consulting applicants, and this post is our ultimate guide for EY and Parthenon interviews.

Below you'll find helpful background on EY, the steps in their interview process, and key skills for succeeding. By following the information below, you'll be one step closer to getting an offer at EY. 

1. EY consulting is bigger than BCG and Bain

If EY's consulting business was spun-off, it would rival the size of MBB firms. With $9.6bn in consulting revenue in 2018, EY's consulting business line is bigger than BCG ($6bn),  Bain ($4bn), and nearly as large as McKinsey ($10bn). 

Over the last few years, consulting services have proven to be an important growth driver for EY and other members of the Big 4. This growth has been fueled through acquisitions, notably EY's acquisition of Parthenon Group in 2014. 

Parthenon was originally founded by former executives from Bain & Company in 1991. The firm grew to model the prestige of MBB firms, but with it's own unique culture (see "smart, nice, driven" below). Fast forward to the 2014 acquisition, which formed the new entity called EY-Parthenon, an EY subsidiary focused on strategy consulting.

To simplify things, EY's broader consulting (or advisory) business can be divided into EY Advisory, and EY-Parthenon:

    • EY Advisory provides 3 primary services which are common at Big 4 firms.
      • Performance Improvement works across industries to help clients create streamlined processes, and powerful systems. For example, helping an international firm like Nike reduce costs, through strategic changes to their supply chain.
      • Performance Technology applies technology solutions to drive business performance. For example, using social media to help a firm like Disney market their vacation resorts, to customers who are already interested.
      • Risk focuses on identifying, evaluating, and addressing risks faced by client businesses. For example, helping a financial institution like Morgan Stanley develop a response plan, to prepare for a data breach.
    • EY-Parthenon focuses on strategy and management consulting. The type of work you'd do here, is very similar to the work you'd find at McKinsey, BCG or Bain.

    If you're interested in applying for a consulting role at EY, then it's important to know what specific area you're interested in. 

    This will help you be more focused in your application, and it will also show your level of preparedness to recruiters. It's not uncommon to be asked about specific areas of interest during interviews, and having a prepared answer using the company's own terms, can really impress your interviewer.

      For the rest of this post, we'll be focusing on the steps you'll need to take in order to land a job in EY-Parthenon. If you're applying for a role in EY Advisory, don't worry. There will likely be some differences, but 95% of the below guide is still relevant, and will provide an excellent overview of the consulting interview process.

      2. EY-Parthenon interview process overview

      EY-Parthenon has 3 steps in their application process.

      1. Resume and cover letter screening
      2. First round interviews
      3. Second round interviews

      These steps outline the typical process. However, for consulting jobs the steps for interviews can vary based on location and role. It can be really helpful to ask your HR contact if they can provide more details on the specific steps for your interview track.

      Generally, your first step will be nailing your resume and cover letter. The recruiter will be looking for specific things on your application, including problem solving and leadership skills. To optimise your documents, check out our articles for consulting resumes and cover letters.

      After the initial application, you'll move onto the interviews. In the first round, you'll typically face a single interview, which is 1/2 case interview, and 1/2 behavioural interview. This is sometimes done in person, and sometimes done over the phone.

      During the behavioural interview portion, they may throw-in a market sizing question, for example: "how many tacos are sold per day in Boston?". So make sure you're prepared for that!

      Second round interviews are usually a "Super Day". Note that the term "Super Day" is usually used in the US, and the term "Assessment Centre" is more common in Europe. This is basically just an on-site office visit, where you perform a series of interviews.

      Super Day (Assessment Centre) overview:

      1. Case interview
      2. Behavioural / fit interview
      3. Group case presentation

      You'll probably just have one of each of these interviews during the second round, but the company values adaptability, so be ready to roll with anything unexpected.

      In the following sections, we'll provide more details on the recruitment steps for EY-Parthenon, including tips and resources for how to prepare.

      3. EY-Parthenon case interviews

      Case interviews at EY-Parthenon are candidate-led. The style is similar to what you will experience in a BCG or a Bain case interview. This is different to firms like McKinsey or Capital One who use interviewer-led cases.

      For a candidate-led case interview, there are 7 types of questions you need to prepare for:

      • Situation
      • Framework development
      • Framework exploration
      • Quant question – Data provided
      • Quant question – No data provided
      • Creativity question
      • Recommendation

      You can read more about case interviews and how to prepare in our free case interview guide. You can also get a sense of what candidate-led case interviews are like, using the video below.

      As we mentioned, case interviews at EY-Parthenon are typically candidate-led and therefore use the same format as BCG and Bain.

      4. Top behavioural interview questions asked at EY-Parthenon

      At EY-Parthenon, there are two main categories of behavioural interview questions:

      1. Fit questions. These are generic questions such as “Why consulting?” or “Why EY?”.
      2. Personal Experience Interview (PEI) questions. These are questions such as “Tell me about a time when you lead a team through a difficult situation.” Or “Tell me about a time where you had to manage a team conflict”

        We've written extensively about consulting fit / PEI questions in the past. But in summary here are the top 5 fit and PEI questions you should prepare for at EY-Parthenon, or other top consulting firms.

        Top 5 fit questions:

        • Why EY?
        • Why consulting?
        • Walk me through your resume
        • Tell me about something not on your resume
        • Tell me about your greatest accomplishment

        Top 5 PEI questions. Tell me about a time when ...

        • You lead a team through a difficult situation
        • You worked in a team and had to manage a conflict
        • You had a disagreement with a colleague / boss
        • You had to change someone's / a group's mind
        • You overcame a really difficult challenge

        If you would like guidance on how to answer PEI questions, you can check our article on the topic here.

        5. EY-Parthenon group case presentation

        As mentioned in the overview above, EY-Parthenon also uses a group case presentation to evaluate candidates during the second round. Here is the key information you need to be aware of for this type of interview:

        • Candidates get divided into groups of 3 to 5
        • Each group is given information about a case (i.e. a client facing a problem)
        • You are given 1 hour to review, and prepare a 15 minute group presentation
        • An interviewer will watch during your prep time, but they won't intervene
        • After your group presents, the interviewers will ask questions for 15-20 minutes

        This interview format is fairly unique, and in addition to your analytical skills, the interviewers will be focusing on your ability to work well with others. 

        Here are the top 4 things you should aim to do:

        • Speak with a purpose. This applies to the preparation and presentation. A lot of candidates will want to speak their mind as they know participating is important. But, participation alone is not enough. The QUALITY of your input is crucial. Sometimes, it's better to let two or three people speak first, and then make a very thoughtful point based on how they started the discussion. Focus more on the quality of your input, and less on the quantity.
        • Involve everyone. During preparation, keep an eye on who's participating in the conversation and who's not. If you identify a member of the group who's struggling to make themselves heard, you should not hesitate to help them by saying something like: "We haven't heard everyone's opinion on this yet. John, Rebecca what do you think?". This is a sign of leadership, and will also help you develop a more thoughtful and balanced presentation. 
        • Summarise. Plan to summarise key points during both preparation and the presentation. This will position you as the person bringing everyone together and making sure all candidates are on the same page. Aim to do this at least once during your prep time. For example, summarise the assignments of each group-member, or recap the group's key points at the end of the 1-hour prep time. This is a skill used by partners in real-world conversations with clients. You can also do this when presenting, by clearly recapping your main points.
        • Anticipate questions. During your preparation, you may notice some weaknesses in your analysis. It's good to carve out 5 minutes, to think through how you would answer challenges from the interviewers. It can also be helpful to ask yourself questions, like "if I was hearing this for the first time, what would I ask about?". The interviewers won't always ask the questions you most expect, but if they do, you'll be prepared with a thoughtful response.

        And the top 4 things you should really avoid doing:

        • Being easy to read. A group interview is a good time to use your poker face. Everyone is stressed, but you need to come across as confident. A good way to do this is to focus on basic body language: look at people in the eye, sit confidently, don't cross your arms, etc.
        • Interrupting others. Consultants need to be client-friendly, and interrupting someone in a discussion is not client-friendly at all. You should listen carefully to what others are saying. Try to have a genuine interest in what they think. Before making your point, summarise their point to show that you understand what they mean.
        • Spending too much time reading. It's important to understand the case materials, but if you're not careful it could consume your full preparation time. A great way to prepare efficiently, is to first scan through the provided materials (just a couple minutes), and to agree upon one or two initial hypotheses. This allows you to then search for specific data points, that confirm or disprove it, before you finalise your approach. 
        • Dominating speaking time. Some candidates are so eager to participate that they end up completely dominating the rest of the group without realising it. Avoid doing this during the 1 hour prep time, and during the presentation itself. Recruiters will be paying close attention to both situations. A practical way of doing this, is to keep an eye on how much time you talk. If you are in a 5-person group you should aim to speak 20% (1/5th) of the time and really no more than 25%. 

        Your performance in individual interviews and the group case presentation will play a big role in the firm's decision to give you an offer. If you'd like to learn more about group case interviews, check out our separate in-depth guide here.

        6. Become really confident at maths

        You don't have to be Rain Man to succeed at case interview maths.  You will be expected to do quick and accurate mental maths during your interview, but with a little practice, it'll become second nature to you.

        In our experience the most successful candidates, review and practice in advance, to gain confidence in their maths skills. This is a critical element of the application process for EY-Parthenon, and having a polished approach will be noticed by recruiters.

        After helping over 30,000 consulting candidates prepare, we've noticed that those who get offers, usually begin with maths preparation. This is the first step candidates take when they enroll in our case interview training programme.

        7. Develop a consistent method to crack cases

        One of the hardest things about interviewing with companies like EY-Parthenon, are the case interviews. Depending on the specific job, you might have as many as 5+ interviews!

        As a result, it’s critical for you to have a consistent approach for solving cases. Case interviews can be broken down into very specific types of questions, including the following:

        1. Situation.
        2. Framework development.
        3. Framework exploration.
        4. Quant question (with and without data).
        5. Creativity question and recommendation.

        If you can crack each type of question (within a case), then you can crack the case.

        One of the most frustrating things about preparing for case interviews, is the lack of a consistent approach for solving each of the case questions. That's exactly why we've created a step-by-step method for solving cases that we teach in our case interview training programme.

        8. Practice cases out loud

        Solving a case is not enough. Recruiters will also be paying close attention to how you COMMUNICATE your answers. You should aim to always speak in a clear and structured way.

        If you can practice with friends or former consultants who do coaching interviews, that's a great approach. However, this isn’t always possible.

        A great alternative, is to simply practice by yourself (out loud). Play the role of both the candidate and the interviewer. That means you should ask questions and answer them, just like two people would in an interview.

        This will probably seem strange at first. But trust us, in our experience candidates who use this approach are much more likely to get an offer.

        9. Learn from every mistake you make

        When it comes to case interview preparation, it's better to do 20 cases thoughtfully, than to rush through 40 cases. A helpful step to make sure you're getting the most out of your preparation time, is to keep a notebook of improvement opportunities for each case.

        That will allow you to address your weaknesses, and then you can check your progress by re-doing old cases. For example, after you have done case #20, you could go back to case #1, to make sure you are not repeating the same mistakes.

        At the end of the day, you'll probably need to put in a minimum of 30 hours, in order to develop good case interview habits. But as with many things in case interviews, quality is more important than quantity.

        10. Smart, nice, driven

        When EY-Parthenon is looking to hire, they have a motto they use to identify the ideal candidate. This motto is "smart, nice, driven".

        You can guess the overarching idea. People within EY-Parthenon are proud of the company's culture, and want their new hires to mesh with this description. From an outside perspective, I think there are two things worth learning from this.

        First, whereas all consultancies place value on being smart and driven, Parthenon elevates the way their people treat others. Here's why this is interesting. If you're drawn to the challenge of a consulting career, but also want some of the relational benefits of a small-firm culture, then EY-Parthenon might be a great fit for you.

        Second, during the interview process, you are likely to encounter this motto. Just by knowing this in advance, you can take steps that will really set you apart from other candidates. Targeting your cover letter to highlight situations in which you embodied these qualities is a great start. You can also be strategic about including these ideas in your interview answers and conversations with recruiters.

        Additional resources

        If you would like to fast track your case interview preparation and maximise your chances of getting an offer at EY come and train with us. More than 80% of the candidates training with our case interview programmes end up getting an offer at their target firm. We know this because we give half of their money back to people who don't.

        You can find a link to our BCG & Bain Case Interview Training Programme below. As mentioned previously, EY uses the same type of case interviews as BCG and Bain. So you can therefore use that programme to prepare for EY.

        BCG & Bain Case Interview Training Programme

        BCG & Bain case interview training programme

        Any questions about EY-Parthenon case interviews?

        If you have any questions about case interviews, do not hesitate to ask them below and we will be more than happy to answer them. All questions are good questions, so go ahead!

        The IGotAnOffer team