Examples
Worked examples
- Is an instance
A grant application includes a theory-of-change diagram with explicit assumptions tagged for testing.
- Is an instance
A programme evaluation revisits the original theory of change to assess where pathways held or broke.
Counter-examples
Looks similar, but isn't
- Not an instance
A theory of change written as a single sentence with no intermediate outcomes or assumptions.
- Not an instance
Treating a ToC as a one-off submission deliverable never revisited.
Editorial commentary
Theory of change (ToC) emerged in evaluation practice in the 1990s, most influentially through the Aspen Institute’s Roundtable on Community Change, and through Carol Weiss’s 1995 argument that programme evaluation needed an explicit account of the causal assumptions linking activities to outcomes rather than just measuring whether outcomes occurred. A theory of change articulates a project’s long-term goals, the intermediate outcomes that must occur before those goals are reachable, the causal pathway connecting each step, and — critically — the assumptions underlying each link, so those assumptions can themselves be examined and tested rather than left implicit.
In research-impact contexts, a theory of change is used for three related purposes: designing an impact strategy before funded work begins, identifying what evidence will actually be needed along the pathway to demonstrate the intended outcomes were reached, and structuring stakeholder engagement around specific points in the pathway rather than treating “impact” as one undifferentiated end goal. Major UK funders (NIHR, ESRC, Wellcome among them) now commonly request a theory of change at grant application stage, distinct from a project’s methods section — the ToC describes why the work is expected to matter and to whom, not how the research itself will be conducted.
A theory of change differs from a simple logic model in the emphasis it places on stated, testable assumptions: a logic model can show inputs leading to outputs leading to outcomes without ever making explicit why each step is expected to lead to the next, where a properly constructed ToC requires each causal link to carry an assumption a reviewer or evaluator could, in principle, check. A one-sentence description with no intermediate outcomes or assumptions, or a ToC diagram produced once for a funding application and never revisited during or after the project, both fall short of what the method is meant to do — a ToC used well is returned to during evaluation to assess where the pathway held and where it broke.
References
- Weiss, C.H., ‘Nothing as practical as good theory’ (1995)
- Center for Theory of Change (theoryofchange.org)
- NIHR impact framework documentation
Also known as
ToC
Machine-readable encodings
Use in your systems
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