Customer Segmentation Framework for Case Interviews: How to Score, Prioritize, and Target

Customer segmentation in case interviews means dividing a market into distinct groups, scoring each on attractiveness and ability to win, then picking one or two targets with quantified rationale. Companies that excel at segmentation grow revenue 15% faster than competitors using undifferentiated strategies (Source: Bain & Company 2024). Segmentation questions appear in roughly 40% of growth and commercial cases at MBB (Source: PrepLounge 2025).

Why Segmentation Appears in Case Interviews

Segmentation is not a standalone case type like profitability or market entry. It appears as a critical step inside broader cases where "who to target" is the binding question. Growth cases ask which segments to prioritize for expansion. Go-to-market cases ask who the primary target is for a new product (Source: PrepLounge 2025).

What separates strong candidates from average ones is the move from description to decision. Average candidates describe segments. Strong candidates score them, rank them, and explain the trade-offs of what they are leaving on the table.

The Five-Step Framework

The segmentation framework has five steps: define the objective, choose dimensions, score segments, prioritize, and activate. Each step builds on the previous one, and skipping any of them is the most common reason candidates lose points (Source: McKinsey Growth Practice 2024).

Framework

Customer Segmentation for Cases

1. 01

   1. Define objective

   Growth, margin, retention, or cross-sell target

2. 02

   2. Choose dimensions

   Need, behavior, value, or channel dimensions

3. 03

   3. Score segments

   Attractiveness and ability-to-win scoring

4. 04

   4. Prioritize

   Select primary and secondary target segments

5. 05

   5. Activate

   Tailored offer, channel, and messaging plan

• Step 1 (Define objective): Clarify whether the goal is revenue growth, margin improvement, retention, or cross-sell. This takes 15-30 seconds but prevents building segments that are interesting but irrelevant.
• Step 2 (Choose dimensions): Use exactly two dimensions to create 3-5 segments. Combine an observable dimension (demographics, geography) with a behavioral or needs-based one. Single-dimension segmentation rarely predicts profitability.
• Step 3 (Score segments): Rate each segment on attractiveness (size, growth, margin, LTV) and ability to win (product fit, CAC, channel access, competitive intensity) using a 1-5 scale or High/Medium/Low.
• Step 4 (Prioritize): Pick one primary target (upper-right quadrant of the 2x2) and one secondary target. Explicitly name what you are deprioritizing.
• Step 5 (Activate): Connect targeting to specific go-to-market actions: product, channel, pricing, and messaging tailored to the chosen segment.

The Four Dimension Families

There are four segmentation dimension families. Harvard Business Review's research on market segmentation found that behavioral and needs-based dimensions outperform demographics for predicting willingness to pay in 73% of studied markets (Source: HBR "Rediscovering Market Segmentation" 2006).

A practical test: if every segment ends up roughly equal in size and attractiveness, your dimensions are not cutting the market usefully. Good dimensions create segments that are clearly different on metrics that matter.

How to Score Segments with a 2x2 Matrix

The scoring step earns the most points in an interview, and it is where most candidates are weakest. Move from qualitative descriptions to quantified scores on two axes (Source: McKinsey Growth Practice 2024).

Attractiveness axis: Segment size, growth rate (annual %), margin quality, customer lifetime value, strategic fit.

Ability to win axis: Product-market fit, channel access, competitive intensity, CAC relative to LTV, switching costs.

Example: B2C fitness app scoring

Recommendation: Serious athletes as primary target: best LTV-to-CAC ratio (6.2x), 8% growth, strong product fit. Corporate wellness as secondary: highest absolute LTV but requires building a B2B sales motion over 12-18 months. Deprioritize rehab (requires clinical partnerships the company lacks).

Worked Example: Online Grocery Segmentation

Case prompt: A European online grocery company with EUR 200M revenue has seen growth slow from 25% to 8%. The CEO wants to reignite growth to 15%+, requiring roughly EUR 14M in incremental annual revenue above the current trajectory.

Dimensions chosen: Order frequency (behavioral) x basket value (value-based).

Primary target: Regular families. Increasing average basket from EUR 62 to EUR 72 through meal-kit bundles generates EUR 38/customer/month. Across 56,000 customers, that is EUR 25.5M annually -- exceeding the EUR 14M gap. Investment: EUR 3M loyalty program. Payback: under 2 months.

Secondary target: Occasional users. Converting 20% (14,000 customers) from 1.4 to 3.0 orders/month adds EUR 12.9M. Investment: EUR 5M in subscription incentives. Payback: 5 months.

Deprioritize: Lapsed customers (high reactivation cost, uncertain return) and incremental investment in power shoppers (already at maximum engagement, low margins from delivery intensity).

Common Mistakes in Segmentation Cases

When to Use Segmentation vs. Other Frameworks

Segmentation is not always the right tool. If the case has a clear quantitative target (why did margin drop 400 bps?), start with profitability. If it asks about market-level attractiveness before you know the customers, start with market entry or 3Cs (Source: IGotAnOffer 2025).

Quiz: Test Your Segmentation Knowledge

Test yourself

1 / 3

Question 1 of 3

A subscription meal-kit company wants to reduce churn. Which segmentation dimension is MOST useful?

• AAge and income (demographic)
• BUrban vs. suburban (geographic)
• CEngagement tier: weekly actives, bi-weekly, monthly, dormant (behavioral)
• DHousehold size (demographic)

Related Framework Guides

• Growth Strategy Case Framework
• Market Entry Framework
• Profitability Framework
• 4Ps Framework in Case Interviews
• 3Cs Framework in Case Interviews
• Value Chain Framework
• MECE Principle Explained
• Case Interview Frameworks Complete Guide

Sources and Further Reading

1. Bain insights on customer strategy and segmentation: bain.com/insights/topics/customer-strategy-and-marketing/
2. McKinsey growth, marketing, and sales insights: mckinsey.com/capabilities/growth-marketing-and-sales/our-insights
3. CFI, customer segmentation overview: corporatefinanceinstitute.com/resources/management/customer-segmentation/
4. PrepLounge, case type identification and frequency data: preplounge.com/en/case-interview-basics/case-cracking-toolbox/identify-your-case-type
5. Harvard Business Review, "Rediscovering Market Segmentation": hbr.org/2006/02/rediscovering-market-segmentation
6. IGotAnOffer, case interview types breakdown: igotanoffer.com/blogs/mckinsey-case-interview-blog/case-interview-types