What is a theory of change?

The short answer

A theory of change is a charity's explanation of why what it does should lead to the change it wants. Not "we help people," but: these activities produce these results, which lead to this outcome, because of these assumptions. It can be one page. Asking for it is the fastest way to find out whether an organization has thought about its own work.

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The phrase sounds academic and the idea is not. It is "why we do what we do," written down, with the steps in between.

The idea was popularized in the 1990s. The argument was that programs fail because their assumptions are never spelled out. Spell them out and you can see which ones are shaky before the money is spent.

In general it has four layers, and the assumptions that connect them.

  • Activities. What the organization does.
  • Outputs. What that produces, counted.
  • Outcomes. What changed for the people it serves.
  • Impact. What that change made possible over time.

Here is a worked example, a food bank.

  • Activities: collect and distribute food.
  • Outputs: 40,000 hampers a year.
  • Outcomes: fewer households in the area skipping meals.
  • Impact: people stable enough to get out of crisis.

The assumptions are the best part. They are: that the people who most need food are the ones who come. That a hamper a week is enough to matter. That food is the problem, rather than rent. A good theory of change names those and says how the organization checks them.

What a good one looks like. For a small charity, a page. For a large one, a diagram with a lot of arrows. Size is not the point. Whether the assumptions are stated is the point, and whether the organization can tell you which one it worries about most.

What a weak one looks like. A list of activities, an arrow, and "a better community." No assumptions, no steps, and no way to be wrong.

What to ask. Walk me through why this should work. Then: which part of that are you least sure of. An organization that has done the thinking answers the second question easily, and usually with some relief.

One caution. A theory of change is a claim, not a result. It tells you the organization has a plan that makes sense. Whether the plan is working is the next question, and it is answered with outcomes, not diagrams.

Questions people also ask

Is a theory of change the same as a logic model?
Close cousins. A logic model is the chart: inputs, activities, outputs, outcomes. A theory of change adds the why, the assumptions that connect each step to the next.
Should a small charity have a theory of change?
Yes, and it can be a single page. What matters is that the assumptions are written down, not how it is formatted.
Does a theory of change prove a charity works?
No. It shows the plan makes sense. Outcomes show whether the plan is working.
Where did the term come from?
Carol Weiss, in a 1995 Aspen Institute publication on evaluating comprehensive community initiatives.

Sources: Center for Theory of Change, What is theory of change and originsWeiss, C. (1995), "Nothing as Practical as Good Theory," in New Approaches to Evaluating Comprehensive Community Initiatives, Aspen Institute