Free Guide to EY-Parthenon Consulting Case Interviews

EY-Parthenon is the strategy consulting practice of the big four accounting firm, Ernst & Young. The company was founded in Boston in 1991 by an ex-Bain consultant and now has 45 offices in 25 countries.

The Parthenon acquisition was made in 2014 and followed similar acquisitions from other Big Four firms Deloitte and PwC who acquired Monitor and Booz & Co respectively.

Every year EY-Parthenon receives thousands of applications for their job vacancies and is known to have a rigorous recruitment process with multiple case interviews.

Selection Criteria: Personality

EY-Parthenon looks for more personality traits than any other strategy consulting firm we have looked at with 10 in total:

  1. Accountable – In the EY-Parthenon strategy practice junior consultants rapidly assume a level of responsibility on their projects. This means that the consultants need to be comfortable with taking accountability for their work when working with senior colleagues and clients.
  2. Adaptable – Strategy consultants work across industries and work on unique problems that do not have an off-the-shelf solution. That means that consultants need to adapt to industries, niches, and problems in order to deliver high-quality solutions for their clients.
  3. Agile – The way that strategy consulting projects are structured means they are fast-paced and constantly changing. Teams that are agile and can flex as priorities change are the most efficient.
  4. Analytical – Client projects typically include an element of data analysis and the datasets are often fragmented and incomplete. EY-Parthenon expects its consultants to be able to able to conduct analysis quickly and competently.
  5. Curious – Each project is different in strategy consulting and requires new research to develop the project team's understanding. Consultants that are naturally curious learn quickly and are motivated to understand new concepts which are hugely beneficial to the project team.
  6. In the know – Interestingly EY-Parthenon places an emphasis on consultants being up to date with current affairs. It benefits their ability to understand the client’s current challenges.
  7. Numbers savvy – With analysis being a common element of strategy consulting projects being numbers-savvy is a non-negotiable for EY-Parthenon. Calculations and analysis often need to be performed at pace.
  8. Resilience – The fast-paced and ever-changing nature of strategy consulting projects means that completed work is often discarded and good work is often morphed by seniors. Resilience and self-belief are required to continually produce work when the reward can sometimes be infrequent.
  9. Strong communication – The concept of upward as well as downward communication is promoted at EY-Parthenon. Communicating workload, estimated delivery times, and when you need further support is imperative to project momentum. Communication is the key to producing high-quality work at a pace.
  10. Team player – All consultants are expected to be good team players as each project will have different team members and there is little time to build rapport and relationships. Good team players can hit the ground running and work effectively in any team.
EY Application Process

There are four stages to the EY-Parthenon application process:

The interview process at EY-Parthenon begins with a resume and cover letter submission online. Their typical recruitment cycle is in the Autumn each year, but they sometimes hire off-cycle, especially at smaller network firms. They are looking for candidates that reflect their desired traits in their applications along with strong academic records and relevant experience.

EY-Parthenon uses an online Numerical Reasoning Test before they invite candidates to interview. The questions follow a similar format to many other online numerical tests. They included data interpretation in the form of graphs and tables with a required calculation.

There are two first-round interviews with junior consultants that consist of one or two fit/experience questions followed by a case interview.

The second round of interviews are with senior consultants and follow the same format as the first round of interviews with fit/experience questions followed by a case interview.

Types of Interviews

EY-Parthenon has three interview formats and questions across their network: experience/fit, case questions, and a written case interview.

Case interview (question)

The case interviews that EY-Parthenon uses are all based on real life client examples. The interviewers are encouraged to use their own client engagements for their case interview questions because they know them well and will be able to provide data and context easily. This format is the most common interview format used by EY-Parthenon because it is the closest resemblance to the work required on the job and allows the interviewer to answer the question ‘Can this person do the work of an EY-Parthenon consultant?’

They assess candidates over a number of different attributes during a case interview:

  • Approach and structure

  • Analytical and creative thinking

  • Application of data

  • Communication skills

  • Business acumen

Scoring well across all these attributes will result in being progressed to the next stage or ultimately, a job offer. For further information on how to demonstrate these skills see our full case interview guide here.

Experience interview

The experience questions are asked prior to beginning the case interview and EY-Parthenon will use questions such as:

  • Why are you interested in EY-Parthenon?

  • Why are you interested in consulting?

  • What experience are you most proud of?

  • What experience do you wish you could do over, and how would you do it differently?

  • What is a difficult decision you have made in the last year?

  • What is an example of a time when you showed initiative and leadership?

  • What aspects of your internship did you like less?

  • What do you most like to do in your free time?

  • What attributes would you bring to a case team?

  • Describe a role where you changed the direction of a team. How did you do it?

The key to these questions is to develop a structure that can be applied to all of them. By structuring your answer, you will show that even when discussing non-business-related topics you apply a considered approach to your answer. Our expert Ian has put together a guide to help you answer some of these experience questions. You may also find this article on the most common consulting interview questions helpful. Just click through the sample questions and get an idea of how you need to approach this part of the application process.

Case interview (structured/written)

The EY-Parthenon structured case interview is similar to the written cases provided at BCG and Bain. The candidate is given an information pack of 15-20 pages and 10 minutes to read the pack with three high-level questions they want to be answered. The interviewer will leave the room in 10 minutes of reading time.

As with the case interview, there is not a correct answer and the important part of your answer is the consideration of trade-offs for making decisions and comparing the possible strategic decisions the business in the question can take. The interviewer will test your thinking and recommendations to see how robust your conclusions are and the steps you took to get there.

EY Parthenon Case Interview

The consulting case interview is the cornerstone of every strategy consulting firm’s interview process due to the ability to replicate the problems and challenges of the work they do.

To score well in an EY-Parthenon case interview, you must meet the criteria laid out above and you can do this following a structured approach to case interviews. The structure of an EY-Parthenon case interview is as follows:

  1. Situation and problem

  2. Hypothesis validation

  3. Framework development

  4. Root cause analysis

  5. Mathematical calculation (sometimes)

  6. Creativity test (sometimes)

  7. Recommendation

At the start of the case, the interviewer will outline the context and the problem to be explored. An example might be:

“A high street retailer wants to cut costs by 30% in response to the Covid-19 pandemic, how would you approach this?”

You would then be expected to put forward an initial hypothesis on the answer and explain your intention to prove or disprove it.

From there you will be expected to develop a framework to conduct your analysis and test it with the interviewer.

If your framework is MECE ("mutually exclusive, collectively exhaustive") and you explore it correctly then you will find the root cause of the issue for the client (in this case where costs can be reduced) and begin calculations if relevant.

The creativity test is when the interviewer asks you for an alternative to your findings or recommendation e.g. “Okay, the client says they do not want to shut stores, how else can they reduce cost?” They may ask this more than once and it tests the candidate's ability to think of alternatives, even if their answer is appropriate.

Finally, you will be asked to provide a recommendation whereby you need to synthesize your findings and give a clear and concise proposal.

For more information on how to approach and solve case interviews, read our full guide here.

EY Parthenon Additional Tips

Fast maths

Case interviews are pressurized situations where your anxiety levels are heightened and you don’t have the safety net of notes or the internet to fall back on.

For in-person interviews, it is common that one of the questions will have a mathematical element or be a market sizing question included. These require long maths calculations without a calculator. If you haven’t practiced long addition, multiplication, division, or subtraction recently, it is good to do so. Being quick at maths shows your competent quantitative skills and reduces unnecessary pressure during the interview, increasing your overall performance.

Practice

As with maths, practicing case interviews is the best way to improve your performance. Through practice, you will begin to develop a robust approach that satisfies the structure and framework components of the case and you will recognize how to navigate the case successfully.

If you are applying to EY-Parthenon then you are probably applying to other strategy consulting firms too, this practice will be relevant to all of the firms you apply to as they all use case interviews in their application process.

Here you can solve a company case from EY-Parthenon and find helpful tips and solutions for this specific case.

Apply structure to everything

The key requirement of a candidate in a case interview is the application of structure, specifically with a MECE approach. As mentioned above, you can even apply structure to the FIT questions and it is recommended you do so.

An example answer to the question ‘walk me through your CV’ would be to segment your experience into: 

  1. Experience relevant to consulting
  2. Experience not relevant to consulting 

and then briefly cover the experience you have in each bucket. This shows you understand what consulting is and what is relevant and also a key skill of a consultant – structured thinking.

If you can demonstrate robust structured thinking in your interview, you will score highly.