The Behavior Change Wheel (BCW) is a comprehensive framework designed to move beyond intuitive, often ineffective, approaches to change intervention design. It was developed from a synthesis of 19 existing frameworks and provides a structured, theoretically informed method for understanding behavior and developing interventions. The framework centers on the Capability, Opportunity, Motivation – Behavior (COM-B) model and the Theoretical Domains Framework (TDF), which help diagnose behavioral influences. The BCW then guides the selection of intervention functions and policy categories, before finally identifying specific Behavior Change Techniques (BCTs). *

The BCW approach systematically enhances the design and effectiveness of interventions by moving beyond intuitive ‘hunches’ or ‘best guesses’. Instead of relying on personal experience or superficial analysis, it aims to ensure that intervention strategies are based on a thorough assessment of the behavioral target, what is needed to achieve change, and how best to implement it. The BCW was developed to reduce reliance on the ISLAGIATT principle (“It Seemed Like A Good Idea At The Time”), where intervention strategies are chosen based on intuition, often leading to ineffective interventions and wasted resources.

The BCW approach includes four behavioral science tools and guides intervention design through a system of five interlinked steps:

Step	Description
Step 1: Behavioral Target Specification	This crucial first step involves defining the problem in behavioral terms, rather than in terms of desired outcomes (e.g., reducing infection rates are outcomes, not behaviors). It requires systematically exploring a system of related behaviors and identifying specific, measurable target behaviors. This precision informs more focused diagnoses and targeted intervention development. Criteria such as likely impact, ease of change, centrality in the system, and ease of measurement guide the selection of target behaviors.
Step 2: Behavioral Diagnosis using COM-B model or TDF	This step involves using theory (COM-B or its elaboration, the Theoretical Domains Framework – TDF) to understand the influences on the chosen behavior and identify what needs to change within the person and/or the environment. The COM-B model posits that behavior (B) occurs when there is Capability (C) to do it (physical or psychological), Opportunity (O) for it to occur (physical or social environment), and sufficient Motivation (M) (reflective or automatic). The TDF further elaborates COM-B into 14 domains, providing a more detailed understanding of potential barriers and enablers. This deep understanding is critical for accurate analysis and designing interventions that effectively address the root causes of behavior.
Step 3: Intervention Strategy Selection using the BCW	Based on the behavioral diagnosis from COM-B/TDF analysis, the BCW framework is used to systematically identify possible “intervention functions” (broad categories of means to change behavior). There are nine such functions: education, persuasion, incentivization, coercion, training, restriction, environmental restructuring, modelling, and enablement. The effectiveness is enhanced by ensuring congruence between the chosen intervention strategy and the behavioral diagnosis; for example, ‘training’ addresses lack of capability but not motivation or opportunity. These potential functions are then narrowed down using the APEASE criteria (Acceptability, Practicability, Effectiveness/Cost-Effectiveness, Affordability, Safety/Side Effects, Equity), which guides decision-making based on available evidence and local context.
Step 4: Implementation Strategy Selection using the BCW	This optional but important step involves considering policy options that would support the long-term implementation of the identified intervention functions. Seven policy categories are identified: communication/marketing, guidelines, fiscal measures, regulation, legislation, environmental/social planning, and service provision. The BCW suggests which policy options are appropriate for each intervention function. These are also evaluated using the APEASE criteria.
Step 5: Selection of Specific Behavior Change Techniques (BCTs) from the BCTTv1	This final step focuses on identifying the precise “active ingredients” that will deliver the chosen intervention functions under the relevant policy options. BCTs are defined as observable, replicable, and irreducible components of an intervention. The Behavior Change Technique Taxonomy v1 (BCTTv1) comprises 93 BCTs organized into 16 groupings (e.g., ‘goal setting’, ‘feedback on behavior’, prompts/cues’). Using BCTs enhances effectiveness by allowing for focused intervention development, improving the reporting and replicability of interventions, and facilitating the identification of active ingredients, which is crucial for cumulative learning and scaling up successful interventions.

The BCW approach is not only for designing new interventions from scratch but also valuable for refining existing ones that have achieved only modest success. By specifying the existing intervention’s BCTs and functions and then conducting a behavioral diagnosis (e.g., using TDF) to identify barriers, theory-based modifications can be proposed to improve their effectiveness.

The BCW approach supports understanding how interventions work (or don’t) by guiding process evaluations, which examine fidelity, implementation quality, causal mechanisms, and contextual factors. This is vital for scalability, replicability, and explaining successes or failures. The COM-B and TDF help explore mechanisms of impact. And the BCW and BCTTv1 can be used to synthesize implementation research, allowing for better characterization of active ingredients and a more helpful accumulation of knowledge on intervention content.

The BCW approach enhances intervention design and effectiveness by providing a robust, systematic, and theory-driven methodology that ensures interventions are precisely targeted, well-structured, evidence-based, and adaptable for both new development and refinement, thereby contributing to more effective behavior change and cumulative scientific learning.

* The Behavior Change Wheel (BCW) and COM-B model were first created for public health, but they’re designed to be practical for everyday use in change situations. They give you a simple way to figure out why a behavior is happening and what to do about it. BCW links that understanding to a set of proven strategies, making it easier to design interventions that are both effective and grounded in science.

Sources:

Michie, S., Atkins, L., West, R. (2014), “The Behavior Change Wheel: A Guide to Designing Interventions”, 1st edition. London: Silverback Publishing.

Michie, S., Richardson, M., Johnston, M., Abraham, C., Francis, J., et al. (2013), “The Behavior Change Technique Taxonomy (v1) of 93 Hierarchically Clustered Techniques: Building an International Consensus for the Reporting of Behavior Change Interventions”, Annals of Behavioral Medicine 46, 81–95.

Michie, S., Van Stralen, M.M., West, R. (2011), “The Behavior Change Wheel: A New Method for Characterizing and Designing Behavior Change Interventions”, Implementation Science 6, 42.