Operations Case Interview (how to prepare)

Operations case interviews aren’t as intimidating as they seem, but to pass, you will need to prepare extremely thoroughly. In this guide, we’ll show you how.

We’ve helped thousands of candidates breeze through their interviews and land roles in consulting, business operations, and other relevant roles at top consulting and tech companies. 

Below, we’ve mapped out the five critical steps you’ll want to follow to get ready. You’ll also find links to free sample cases from leading consultancies, plus other deep-dive resources for solving case interviews. 

Here’s a brief overview of what we’ll cover:

1. Learn what to expect in an operations case interview
2. Know the different types of operations case interview problems
3. Solve practice cases
4. Learn a structured approach to solving cases
5. Prepare for your operations case interview

Let’s get started!

1. Learn what to expect in an operations case interview↑

1.1 What is an operations case interview?

Operations case interviews, also known as operations case study interviews, test candidates on their ability to analyse and improve business processes. 

There are many types of case interviews, but operations cases are especially common at firms with strong ops practices like McKinsey, BCG, Bain, Deloitte, Accenture, or Kearney. They also sometimes come up in interviews for business operations and strategy (BizOps) and product operations roles. 

During the interview, candidates are presented with a case study about an imaginary company facing an operational challenge in areas such as supply chain, production, staffing, or customer service.

Here, you’ll be expected to develop your own framework that leads to a feasible recommendation based on the operational, technical, and business context of the case.

To succeed in operations case interviews, you’ll need strong analytical and quantitative skills, as well as practical knowledge of operational levers such as optimisation, supply chain management, and process improvement.

1.2 Strategy vs Operations Case Interviews

Both strategy and operations case interviews are common across roles in consulting, BizOps, and product operations. But they test different skill sets and tend to come up based on the specific role, team, or office you’re applying to.

According to James, ex-senior manager at BCG, strategy cases focus more on “what direction the company should take,” while operations cases are more concerned with “how to improve performance within existing constraints.”

Strategy interviews typically involve long-term business decisions, such as entering a new market, launching a product, or adjusting pricing. These cases are broad and often ambiguous, requiring strong business judgment and the ability to evaluate trade-offs at a high level.

Operations case interviews, by contrast, focus on how a business runs day to day. James says these problems usually involve creating short-term fixes and making real-time trade-offs. “You’re diagnosing inefficiencies rather than exploring strategic options, which demands sharper analytical breakdowns and more detailed logic trees.” 

Operations case interviews also tend to be more data-heavy and math-intensive. Candidates are expected to analyse numbers and interpret data, as well as “dive into KPIs like throughput, utilization, downtime, or unit costs, not just revenue growth or market share,” says James. 

2. Know the different types of operations case interview problems↑

Operations case interview problems used at the top consulting firms are generally one of the following:

• Production optimisation - focuses on increasing a company’s output by improving how resources are used across its operations
• Process improvement - involves analysing workflows to find bottlenecks or redundancies and suggesting practical improvements.
• Cost-cutting - challenges you to reduce spending without hurting performance or disrupting core operations
• Forecasting and capacity planning - asks you to estimate future demand and determine how much to produce, staff, or stock to meet it 

Keep in mind that the exact categories and terms may vary depending on the company you're interviewing for. But the core skills being tested are no different. 

At McKinsey, for example, operations cases may be classified as: cost reduction, capacity management, quality improvement, or supply chain optimisation.

Right, let’s get into some practice cases. 

3. Solve practice cases↑

The best way to master solving the different types of operations case interviews we've outlined above is to practise with realistic example cases. 

Below, we’ll dig deeper into the broader categories to give you a clearer idea of what problems to expect. We’ll also share operations case samples from top consultancies and real Glassdoor examples from our BizOps guide, which align closely with MBB-style interviews. 

For categories where real examples aren’t available, we’ve created sample scenarios that reflect the kinds of problems candidates typically face.

3.1 Production optimisation 

First up are production optimisation cases. These problems focus on increasing the output or production of a business within a given timeframe using the resources they already have.

Here, the interviewer wants to see if you can break down a production process, understand performance issues, and recommend ways to increase output efficiently. 

You’ll also be crunching numbers. So, it helps to be familiar with formulas for solving utilisation, capacity, and cycle time.

Give it a try using the sample case below. 

3.2 Process improvement

Businesses need efficient processes to deliver products and services faster, more reliably, and at a lower cost. 

In process improvement cases, you’ll be asked to break down a complex process and identify pain points that affect cost, quality, or customer experience. The goal is to be able to propose changes across people, tools, or workflows that lead to measurable improvements in performance. 

Use the samples below to get comfortable with these types of cases. 

3.3 Cost-cutting

Cost-cutting cases challenge you to help a company reduce spending while staying operational. You’ll need to distinguish between core business expenses and discretionary costs, then recommend where cuts can be made without hurting performance.

That means understanding the business well enough to spot where money is being wasted, and recognising where trade-offs between cost, quality, and performance make sense.

3.4 Forecasting and capacity planning

Our last category requires you to estimate how much a company should produce, staff, or stock to meet future demand. 

Forecasting and capacity planning cases test your ability to make informed decisions based on uncertain or fluctuating demand. You’ll need to balance the risks of doing too much versus too little, whether that means overproducing, understocking, or understaffing.

To solve these cases, you should be familiar with demand estimations, underage/overage costs, and how to calculate or optimise production and inventory levels across industries.

Since there are no publicly available cases in this category, we’ve put together a few sample scenarios to give you a sense of the kinds of questions interviewers might ask.

4. Learn a structured approach to solving cases↑

Whichever type of case you're given, you can follow this structured approach. Keep in mind that this is just a guide. You should ALWAYS customise your frameworks based on the specific case prompt, company, and role you’re interviewing for.

1. Ask clarification questions
2. Create a case framework
3. Explore the framework
4. Do the maths
5. Brainstorm
6. Make a recommendation

Let's dive into each step:

4.1 Ask clarification questions

As the interviewer lays out the case problem, you need to snap into full concentration mode. You'll need to write down all the key points from the information they give you, and once you've got it down, summarise the problem back to the interviewer.

This has two benefits: it's a great way to make sure you've properly understood the most important details, and it gives you some thinking space to think of clarification questions.

There will ALWAYS be clarification or follow-up questions worth asking. For example, imagine you’re given a case where you need to help a factory improve its on-time delivery rate. You could ask:

• What’s the current on-time delivery rate?
• How is the delivery process structured today?
• Where in the process are most delays happening: production, packaging, or logistics?
• Is the client more concerned with improving speed, consistency, or cost efficiency?

4.2 Create a case framework

It’s time to structure your thinking. A clear framework will guide your approach for the rest of the interview and show you can break down complex problems into manageable parts.

The kind of framework you create will depend on the type of case problem you're given, but most of the time, you'll create an issue tree. You'll need to make sure that your issue tree is both MECE and 80/20. 

Then, you can base your issue tree using one of the top 7 case interview frameworks, but don’t copy them word-for-word. 

Interviewers can immediately spot and penalise candidates who do this because the objective of the framework question is to test your creativity and business acumen, not your ability to memorise frameworks!

Once you've created your framework, talk the interviewer through it.

4.3 Explore your framework

Once you’ve laid out your framework to the interviewer, start working through it. The best way to do this is usually by making a hypothesis. 

State a hypothesis that seems most likely, given the information available, and test it as you go. Think aloud as you start exploring this hypothesis. 

Ask the interviewer questions to explore whether your hypothesis is valid. If you conclude that your hypothesis is false, eliminate that branch and go to the next one.

4.4 Do the maths

Now you're deeper into the analysis of the case, it's almost certain that you'll come across some calculations that you need to make.

You might be provided with additional charts and data (McKinsey) or you might be asked a quantitative question with no data provided (BCG, Bain), such as “Can you estimate how many units the factory can produce in a week?” or “What’s the cost impact of reducing downtime by 10%?”

Calculators are not usually allowed in case interviews. This applies to both in-person and virtual case interviews. That’s why candidates must practice doing mental maths quickly and accurately before attending a case interview. 

Unfortunately, doing calculations without a calculator can be really slow if you use standard long divisions and multiplications. 

Luckily, there are some tricks and techniques that you can use to simplify calculations and make them easier and faster to solve in your head. We cover them in our free guide to Case interview maths.

After doing the math, interpret your results and explain what they mean for the business.

4.5 Brainstorm solutions

Depending on the type of operations case problem you're given, you may reach a moment near the end of the case where you're required to brainstorm potential solutions, problems, or causes.

For example: Now that we know the delivery delays are happening at the packaging stage, what are some ways the client could speed up that part of the process?

This kind of question is very open-ended. There are no right or wrong answers. It’s testing your ability to think creatively under pressure, while still being structured in your approach.

When you get to this stage, take a minute to collect your thoughts and build a simple framework before answering.

Your “framework” here can be very basic. For instance, in the example above, you might split your ideas into two buckets: process changes and staffing improvements. Then, suggest a few ideas under each. 

That way, your thinking stays organised and easy to follow.

4.6 Make a structured recommendation

The last component of every case interview is the recommendation. As the name suggests, this is the part of the interview where you’ll be asked to summarise your findings and explain what the client should do.

When asked to give your recommendation, don't jump straight in. Ask for a moment to gather your thoughts. Then:

• Give your recommendation first
• Then provide 3-5 supporting arguments
• Outline next steps and potential risks

According to James, most candidates make the mistake of ignoring bottlenecks, resource limitations, or timelines when making recommendations. This often results in proposals that sound good in theory but fall apart in practice.

To avoid this, always think of the bigger picture and ask yourself what can realistically be changed within the client’s context. This way, your recommendation remains grounded, actionable, and aligned with the constraints the client is facing.

If you’re interviewing for a strategy and operations role, check out our BizOps interview guide for a step-by-step breakdown of how to answer a real case question from Glassdoor. The example is based on a strategy case, but the same framework applies just as well to operations problems.

5. Prepare for your operations case interview↑

5.1 Practise by yourself

We recommend that you practise by interviewing yourself out loud. Play the role of both the candidate and the interviewer, asking the questions and answering them, just like you would in an interview.

This may sound strange, but it will help you master the rhythm of case interviews. It will also help you to memorise the key details of your answers to behavioural questions, without any crutches (like notes, glancing at your resume, etc.).

If you’re looking for more practice questions, check out our consulting interview prep guide if you're targeting consulting roles, or our BizOps interview guide if you're preparing for strategy and operations roles.

Of course, by yourself, you can’t simulate thinking on your feet or the pressure of performing in front of a stranger. Plus, there are no unexpected follow-up questions and no feedback.

That’s why many candidates try to practice with friends or peers.

5.2 Practise with peers

If you have friends or peers who can do mock interviews with you, that's an option worth trying. It’s free, but be warned, you may come up against the following problems:

• It’s hard to know if the feedback you get is accurate
• They’re unlikely to have insider knowledge of interviews at your target company
• On peer platforms, people often waste your time by not showing up

For those reasons, many candidates skip peer mock interviews and go straight to mock interviews with an expert. 

5.3 Practise with experienced ex-interviewers

In our experience, practising real interviews with experts who can give you company-specific feedback makes a huge difference.

Find an operations interview coach or a consulting interview coach so you can:

• Test yourself under real interview conditions
• Get accurate feedback from a real expert
• Build your confidence
• Get company-specific insights
• Learn how to tell the right stories, better.
• Save time by focusing your preparation

Landing a job at a big tech company often results in a $50,000 per year or more increase in total compensation. In our experience, three or four coaching sessions worth ~$500 make a significant difference in your ability to land the job. That’s an ROI of 100x!

Click here to book case mock interviews with experienced interviewers.