Module 10 · The science in depth · Conceptual framework

COM-B and the Behaviour Change Wheel

Capability, opportunity and motivation — a way to diagnose what is missing.

6 min read · Level: Advanced · Free — no account needed to read

The problem it solves

When a behaviour isn’t happening, what exactly is missing?

The concept

The COM-B model says behaviour happens when three things are present: Capability (the skills, knowledge and physical ability), Opportunity (the time, resources, surroundings and social support), and Motivation (the wanting, planning and habits that energise action).

It’s a diagnostic lens. If someone isn’t cooking at home, is it capability (they don’t know how), opportunity (no time, no kitchen, family pressure) or motivation (they don’t want to, or it isn’t a habit)?

The Behaviour Change Wheel then links each missing component to types of intervention. You don’t need the whole wheel to use the core question.

Why it matters

Many habit failures come from treating an opportunity or capability problem as a motivation problem — trying to want something more when the real barrier is time, space or skill.

Conceptual framework: A way of organising ideas that helps you think clearly. It describes rather than predicts, so it is judged by how useful it is.

See it happen

Kaia keeps promising herself to swim weekly and doesn’t, and decides she’s unmotivated.

The ordinary first approach

She needs more motivation to swim.

With the idea

Using COM-B she finds the barrier is opportunity: the pool’s adult sessions clash with her work. She finds an early-morning session.

What changed

She fixed the missing component instead of blaming her motivation.

Easy to get wrong

• Assuming every barrier is about motivation.
• Ignoring social opportunity — what people around you make easy or hard.
• Using the model to label people rather than to find barriers.

Try it now: Run a COM-B check

1. Pick one habit that isn’t happening.
2. Ask: capability? opportunity? motivation? Write what’s missing under each.
3. Choose one fix for the biggest gap.

Apply it to one of your habits

For one of your habits, which is missing most right now — capability, opportunity or motivation?

Reflect

• Which barrier did you think was motivation but wasn’t?

Go deeper — evidence & sources

• Michie, van Stralen & West (2011). The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implementation Science. doi:10.1186/1748-5908-6-42
• The Behaviour Change Wheel — Susan Michie, Lou Atkins & Robert West (2014)