85% of top-tier consulting firms use case studies as their primary evaluation criterion.
Case study interviews are the key to your consulting career at McKinsey, BCG & Co.
Consulting case studies are considered one of the most challenging interview formats ever. You must solve complex business problems under time pressure, think structurally, and communicate convincingly at the same time. But with the right framework and sufficient practice, you will master this challenge. In this guide, you'll learn everything you need for successful case interviews.
What are Case Study Interviews?
Case studies simulate real consulting projects in compressed form. You solve a business problem within 20-45 minutes.
Not monological presentation, but structured discussion
Breaking down complex problems into manageable components
Real business situations from consulting practice
Types of Case Studies
Understand the different case types and prepare specifically:
Estimate and calculate market sizes
How big is the coffee market in Germany? Such questions test your analytical thinking and ability to break complex problems into smaller parts.
Approach:
- • Define market boundaries
- • Choose estimation approach
- • Make transparent assumptions
- • Plausibility check
Strategic business decisions and market entry
Should a company enter a new market? These cases combine strategic thinking with market analysis.
Approach:
- • Analyze market attractiveness
- • Assess competitive intensity
- • Evaluate own capabilities
- • Decision recommendation
Optimize business operations
How can a company increase its efficiency? These cases focus on process optimization and operational excellence.
Approach:
- • Map current processes
- • Identify bottlenecks
- • Develop solutions
- • Quantify improvements
The STAR Framework for Case Studies
A proven structured approach that helps you work through any case systematically.
Define the problem and capture context
Wichtige Aktionen:
- • Listen actively to all information
- • Take structured notes
- • Ask clarifying questions
- • Define success criteria
Choose framework and create work plan
Wichtige Aktionen:
- • Choose appropriate analysis framework
- • Break problem into sub-areas
- • Formulate hypotheses
- • Prioritize analysis steps
Systematic analysis and data evaluation
Wichtige Aktionen:
- • Work through frameworks methodically
- • Perform quantitative calculations
- • Make assumptions transparent
- • Validate interim results
Structure insights and summarize
Wichtige Aktionen:
- • Prioritize key insights
- • Derive action recommendations
- • Quantify business impact
- • Define next steps
Practice Cases with Sample Solutions
Three fully developed cases that reflect typical consulting interviews.
A US e-commerce giant wants to expand into Germany
Problem Statement:
Estimate the size of the German e-commerce market for electronics and assess the potential for a new market participant.
Approach::
Market Definition
Define the relevant market boundaries
- • Define electronics products (smartphones, laptops, etc.)
- • Geographic boundary: Germany
- • Time period: Current year
- • B2C focus (no B2B sales)
Top-Down Estimation
Macroeconomic approach
- • German GDP: ~3.8 trillion euros
- • Private consumption: ~55% of GDP = 2.1 trillion euros
- • E-commerce share: ~15% = 315 billion euros
- • Electronics share: ~8% = 25 billion euros
Bottom-Up Validation
Consumer-based verification
- • 83 million inhabitants in Germany
- • ~70% buy electronics online = 58 million
- • Average spending: ~430 euros/year
- • Market size: 58M × 430€ = 25 billion euros
Key Insights:
- The German e-commerce market for electronics is approximately 25 billion euros
- Strong market fragmentation offers opportunities for new providers
- Mobile commerce is growing above average (+25% YoY)
- Preference for established brands requires strong trust building
A clothing chain has been losing money continuously for two years
Problem Statement:
Identify the causes of losses and develop a turnaround plan.
Approach::
Profit Diagnosis
Systematic analysis of profit structure
- • Analyze revenue development (number of stores × revenue/store)
- • Break down cost structure (COGS, personnel, rent, etc.)
- • Review development over time
- • Benchmark with competitors
Root Cause Analysis
Identify main problems
- • Declining customer traffic (-15% over 2 years)
- • Decreasing conversion rate (-8%)
- • Disproportionate cost growth (+12%)
- • Inventory management problems (high write-offs)
Solution Options
Strategic action alternatives
- • Digital transformation (online + mobile)
- • Store optimization (smaller, more profitable spaces)
- • Supply chain efficiency (better demand forecasting)
- • Cost reduction (personnel optimization, rent negotiations)
Key Insights:
- Main problem: Missing omnichannel strategy in digital transformation
- Rapid implementation of digital solutions required (6-12 months)
- Store portfolio: 20% of branches cause 60% of losses
- Investment of 15M euros could achieve profitability in 18 months
Your Path to Case Interview Success
Case studies require intensive preparation, but with the right methodology and sufficient practice, you will master this challenge. Remember: it's not just about the perfect answer, but about structured thinking and professional communication.
Ready for Your Case Interview?
Use our tools and resources to prepare optimally for consulting interviews.