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Theory of change

How do I develop a theory of change?

Category: EvaluationName: Dawn Sellers, Project Officer
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“Identifying a theory of change helps to  articulate what we want to be different in five years, which helps improve momentum at the start and clarity of purpose towards the end.”  


At the beginning of a project it’s important to develop a theory of change (sometimes called a results chain) and conceptual model while you’re developing your overall aims, goals and objectives. It’s a good idea to have a vision of where the project is going from the beginning of the project. A conceptual model represents a set of relationships between factors that are believed to impact one (or more) of the project targets. The conceptual model portrays graphically the situation of your project and provides the basis for determining where you can intervene with your strategic activities, and can be shown in a separate theory of change diagram. A theory of change diagram sets out how your project will address the threats identified in the conceptual model.

Developing a theory of change

A conceptual model and theory of change should be accompanied by a textual description that explains the diagrams. It’s useful to have these discussions at the beginning of the project and use them to formulate your project proposal. The diagrams can then be reviewed throughout the project to ensure you’re on track to deliver what you set out to and to determine if there are any new threats or factors (or ones that you may have missed in your earlier model) that are now affecting your targets. If so, you will need to make decisions about if and how you will address them.

Step by Step

  1. Start by developing the project’s goals, aims, targets and objectives.
  2. As a team, identify the direct and indirect threats, as well as the opportunities
  3. Work backwards from each of the threats (i.e. what’s causing the threat) – making links and connections between factors. This will give you a conceptual model.
  4. Use the conceptual model to develop a theory of change for how you will address each of the threats – working backwards from the project target.
  5. Finish by writing a narrative to explain your theory of change.

Top Tips

Create your theory of change at the start. It’s good practice to have a team discussion on the project’s conceptual model and theory of change right at the beginning of the project. This will ensure that everyone understands what the project is trying to achieve, and allows them to see how their role and work fits in the wider project goals. The development of a project theory of change should be a team effort.


Include ideas on how the project outputs will last beyond the end of the project. It’s not enough to create something – a report, a website.  There needs to be plenty of time assigned to ‘embedding’ that resource into everyday use.  Part of this comes down to developing something people need, something useful!  But it also about getting those outputs in the right hands, demonstrating how they can be used and helping them become an important part of everyday working whether that be a management plan or an information resource.  Creating an ‘exit strategy’ as part of the project plans will help make the results self-sustaining.



Ideally develop a theory of change to guide the development of a project proposal. Then once the project has started dedicate a full 2 days to discuss the conceptual model and theory of change as a team, followed by annual review sessions to check the diagram still holds true.


You will need to involve the whole team to develop the conceptual model and theory of change – including external partners. These diagrams are for internal use only, and should not be shared with external stakeholders.


The computer programme Miradi