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MODULE 2 · MARKET · TOOL 05

Market Segmentation

A market of 12,000 companies isn't a target — it's a crowd. Segmentation splits it into distinct groups that respond differently, so you can choose who to serve first.

▸ Try the interactive tool
SolvesOne-size-fits-all targeting that resonates with no segment.
Category · Market Analysis Complexity · Mid Time to apply · 1–2 days Pairs with · TAM/SAM/SOM · Personas
A WHAT IT IS

The framework

Market segmentation divides a broad market into sub-groups of customers who share similar needs, behaviours, or characteristics — and who will therefore respond similarly to a product, price, or go-to-market approach. A market of thousands of companies is not a segment; it's a market. Segmentation turns it into distinct, prioritisable groups.

The point isn't to describe everyone — it's to choose. Different segments want different things, pay differently, and are reached differently. Trying to serve all of them equally produces a product that fits none of them well. Good segmentation makes the trade-offs visible so you can deliberately pick a beachhead, and a useful segment is one where the members behave similarly and differently from other segments.

TRY IT

Try it yourself

B WHY IT MATTERS

What it prevents

Without segmentation, “our customer” is an average that describes nobody — and a product built for an average fits no real person.

The shortcutWhat it costsWhat it gives you instead
Treating the market as oneYou build for an average user who doesn't exist; the product pleases no one fully.Segments group people who actually behave alike, so you can fit one well.
Segmenting by demographics only“Companies with 50–200 staff” may behave totally differently internally.Behavioural and needs-based segmentation predicts response better than size alone.
Too many micro-segmentsSlicing into twenty groups paralyses prioritisation.A handful of meaningful segments keeps the choice tractable.
Never choosingSegmenting but then serving everyone defeats the purpose.Segmentation exists to pick a beachhead — the choice is the output.
C HOW TO RUN IT

Step by step

1

Pick segmentation variables that predict behaviour

Choose dimensions that actually change how customers respond — needs, jobs, buying behaviour, context — not just demographics. The test: do members of a segment behave alike?

2

Divide the market into candidate segments

Group the market by those variables. Aim for a handful of distinct segments, each internally similar and externally different.

3

Profile each segment

For each, capture size, needs, willingness to pay, and reachability. This is what makes them comparable when you prioritise.

4

Score and prioritise (e.g. MADA-style)

Rate segments on attractiveness (size, growth, fit, reachability) and pick where to focus. Not all viable segments are worth pursuing first.

5

Choose the beachhead

Commit to the segment you'll serve first and best. The others aren't abandoned — they're sequenced behind a deliberate first choice.

D IN PRACTICE

A short illustration

IN PRACTICEbeachhead choice

A team treated its whole serviceable market as one audience and built broadly. Conversion was mediocre everywhere. Segmenting by behaviour rather than company size revealed that one group had an urgent, specific need while the rest were merely curious.

The urgent group was smaller but converted far better and churned far less. Focusing the product and messaging on that beachhead — rather than the bigger, lukewarm crowd — turned mediocre metrics into strong ones, and gave a credible base to expand from later.

The lesson: the biggest segment is rarely the best beachhead. The right first segment is the one with the most urgent need and the best fit — strength in one segment beats mediocrity across all of them.
E THE ARTIFACT

The prioritised segment map

The deliverable is a comparison of segments scored for attractiveness, with the chosen beachhead marked.

Segment dimensionWeak basisStrong basis
What you split onDemographics aloneNeeds & behaviour
Number of segmentsTwenty micro-slicesA handful, distinct
What you captureJust sizeSize, need, pay, reachability
The outputA descriptionA chosen beachhead
F THE SO-WHAT

Why it matters

THE KEY INSIGHT

Segmentation isn't a describing exercise — it's a choosing exercise. Its whole purpose is to make you pick a beachhead instead of diluting effort across a market that only looks like one audience.

The hard discipline is segmenting on what predicts behaviour, not what's easy to measure. Company size and demographics are convenient but often don't predict how a customer responds; needs, jobs, and buying context do. A team that segments by behaviour finds groups that genuinely react differently — and a group that reacts differently is one you can win deliberately, rather than hoping the average works out.

G MISTAKES & LIMITS

Common mistakes

Demographics as the only lens

Easy to measure, weak at predicting response. Layer in needs and behaviour.

Too many segments

Over-slicing paralyses the very choice segmentation is meant to enable. Keep it to a few.

Segmenting then serving everyone

If you don't pick, you've done analysis without a decision. Choose the beachhead.

Static segments

Markets evolve; segments drift. Revisit them as you learn.

When not to use it

H CONNECTS TO

Where this sits in the toolkit

Feeds → TAM/SAM/SOM

Your SAM is defined by which segments you can serve; segmentation draws those lines.

Feeds → Personas

A chosen segment becomes a persona (Tool 12) — the concrete, human face of the abstract group.

Informs → Positioning

You position for a segment, not a market — Dunford's framework (Tool 15) starts from the segment you chose.

Connects to → GTM

Different segments need different go-to-market motions (Tool 22); the beachhead choice shapes the motion.

TRY IT YOURSELF

Re-segment a market by behaviour

Take a market you know that's usually described by size or demographics. Re-split it by how customers actually behave or what job they're hiring the product for.

Identify which behavioural segment has the most urgent need — not the biggest headcount.

That urgent-need segment is almost always the better beachhead, even when it's smaller than the obvious demographic slice.