In last month’s newsletter, we explored the COM‑B model of behaviour change. This month, we turn to the Behaviour Change Wheel, a practical framework that builds on COM‑B and helps us understand why people behave as they do and how we can support meaningful, sustainable change. Developed by Susan Michie, Maartje van Stralen, and Robert West, the Behaviour Change Wheel brings together nineteen behaviour‑change theories into one coherent model. It is widely used across health, community work, and organisational development because it offers a clear, structured way to design interventions that are both evidence‑based and realistic.
To show how the model works in practice, we will use a worked example: a community health team aiming to help inactive adults become more physically active. Rather than leaping straight to solutions, the Behaviour Change Wheel encourages a systematic approach that begins with understanding the behaviour itself.
The COM‑B model: The centre of the wheel
At the centre of the Behaviour Change Wheel is the COM‑B model, which proposes that a behaviour will only occur when a person has the capability, opportunity, and motivation to perform it. Capability includes both physical and psychological ability. Opportunity refers to external factors such as time, resources, social support, and environmental cues. Motivation includes reflective processes such as conscious decision‑making, as well as automatic processes like habits, emotions, and impulses. Behaviour rarely arises from a single cause; instead, it emerges from the interaction of all three components.
Worked example step 1: Conducting the COM‑B diagnosis
The first step is to understand why the desired behaviour is not happening. In our example, the team begins by analysing capability, opportunity, and motivation among adults who are currently inactive.
Many people report low psychological capability. They are unsure how much activity they need, what counts as exercise, or how to begin safely if they have health conditions. Some also lack physical capability, such as confidence in their balance, mobility, or strength. Opportunity plays a major role too. People often describe limited time, few local facilities, or a lack of someone to be active with. Social opportunity is also influential; if friends, family, or colleagues are inactive, it becomes harder for an individual to break the pattern.
Motivation is mixed. Some people have low reflective motivation because they do not see physical activity as a priority or doubt that it will make much difference. Others struggle with automatic motivation, feeling anxious about exercising in public, recalling negative experiences of PE at school, or finding sedentary habits more comfortable and familiar.
By mapping these barriers, the team gains a clear picture: knowledge gaps, low confidence, limited social support, environmental constraints, and mixed motivation all contribute to inactivity.
The nine intervention functions: The middle layer
Once the COM‑B diagnosis is complete, attention turns to the nine intervention functions in the middle layer of the wheel. These represent broad categories of strategies that can influence behaviour. Education builds knowledge and understanding, while training develops the practical skills people need to act. Persuasion helps shift feelings and attitudes, and incentivisation encourages change by offering rewards. In contrast, coercion introduces the possibility of penalties, and restriction limits opportunities to engage in harmful behaviours. Environmental restructuring changes the physical or social setting so that the desired behaviour becomes easier, while modelling provides relatable examples for people to follow. Finally, enablement removes barriers and offers extra support when education or training alone is not enough.
Each function works in a different way, targeting specific aspects of capability, opportunity, or motivation.
Worked example step 2: Selecting intervention functions
The team selects intervention functions that directly address the barriers identified. Education is needed to improve understanding of recommended activity levels and safe ways to begin. Training can help people develop basic movement skills such as balance, mobility, or strength. Environmental restructuring may involve creating safe walking routes, improving lighting, or offering beginner‑friendly classes at accessible times. Modelling can be used by showcasing relatable local role models who have successfully increased their activity. Persuasion may help shift attitudes by highlighting enjoyable aspects of movement rather than focusing solely on health risks. Enablement is important for those facing multiple barriers, offering additional support such as tailored activity plans or buddy systems.
By selecting functions that match the COM‑B diagnosis, the intervention becomes targeted rather than generic.
The seven policy categories: The outer layer
The outer layer of the Behaviour Change Wheel contains seven policy categories. These represent the wider systems and structures that can support or deliver the chosen intervention functions. Communication and marketing share key messages through mass media, digital channels, or printed materials, while guidelines set out recommended standards for organisations, services, or professional practice. Fiscal measures use costs, subsidies, or financial incentives to make certain behaviours more or less affordable. Regulation introduces rules or standards that guide individual or organisational behaviour, and legislation creates or changes laws to formalise requirements, restrictions, or penalties. Service provision ensures that people have access to the practical support they need, such as health, education, or community services. Finally, environmental and social planning shapes places and communities so that healthier or more desirable behaviours are easier to adopt.
Behaviour change is rarely achieved through individual effort alone; supportive systems make change more possible and more sustainable.
Worked example step 3: Identifying policy categories
To deliver the intervention effectively, the team considers which policy categories are most relevant. Communication and marketing can be used to run a local campaign promoting simple ways to be active. Guidelines may be developed for workplaces, encouraging short movement breaks or active travel options. Fiscal measures could include subsidised exercise classes or reduced‑cost gym memberships. Regulation might involve ensuring new housing developments include safe walking paths. Service provision is essential, such as offering community‑based activity groups or supervised sessions for beginners. Environmental and social planning can support long‑term change by designing parks, pavements, and community spaces that encourage movement.
These policy categories ensure the intervention is supported by wider systems rather than relying solely on individual behaviour change.
Strategic decision‑making: The APEASE criteria
To choose the most appropriate combination of intervention functions and policy categories, the Behaviour Change Wheel uses the APEASE criteria: affordability, practicability, effectiveness, acceptability, side effects, and equity. These criteria help practitioners evaluate whether an intervention is realistic, ethical, and fair, and they encourage consideration of unintended consequences and the importance of reducing inequalities.
Worked example step 4: Applying the APEASE criteria
Before finalising the intervention, the team evaluates each option using the APEASE criteria. They consider affordability by checking whether subsidised classes fit within the local budget. Practicability is assessed by examining whether staff and facilities are available to run beginner sessions. Effectiveness is estimated using evidence from similar programmes. Acceptability is explored by consulting community members to ensure the approach feels welcoming and inclusive. Potential side effects are considered, such as whether promoting gym memberships might exclude those who prefer outdoor activity. Equity is examined to ensure the intervention supports groups who face the greatest barriers, such as older adults, people with disabilities, or those living in deprived areas.
This step ensures the final plan is realistic, ethical, and fair.
Worked example step 5: Bringing it all together
The final intervention might include clear educational materials, beginner‑friendly training sessions, improved walking routes, positive role modelling through local stories, and supportive services such as activity buddies or tailored plans. These would be delivered through coordinated communication campaigns, workplace guidelines, subsidised classes, and thoughtful environmental planning. By following the Behaviour Change Wheel, the team moves from understanding the behaviour to designing a structured, evidence‑based intervention that addresses real barriers and supports long‑term change.
Overall, the Behaviour Change Wheel provides a clear, systematic way to move from understanding a behaviour to designing a targeted intervention. It encourages structured thinking, avoids guesswork, and helps practitioners appreciate the complexity of behaviour change while offering a practical tool that can be applied in real‑world settings.
Links
Michie, S., van Stralen, M.M. and West, R. (2011) ‘The behaviour change wheel: a new method for characterising and designing behaviour change interventions’, Implementation Science, 6(42).
Beltrani, A. (2023) ‘Behavior Change Wheel’, The Business of Practice, Palo Alto University. Available at: https://paloaltou.edu/resources/business-of-practice-blog/behavior-change-wheel (Accessed: 17 August 2026).
ModelThinkers (n.d.) COM-B & Behaviour Change Wheel. Available at: https://modelthinkers.com/mental-model/com-b-behaviour-change-wheel (Accessed: 17 August 2026).
