Updated: May 26, 2021
The "Theories of Change" chapter in Advocacy Organizing, describes different high-level forces that shape society and history. But the term "Theory of Change" is also used to describe the narrower process of describng a specific desired change and then working backwards through all the steps needed to make it real. Wikipedia, of all places, has a concise and useable description of this powerful process. Here's the introduction:
"Theory of Change (ToC) is a specific type of methodology for planning, participation, and evaluation that is used in companies, philanthropy, not-for-profit and government sectors to promote social change. Theory of Change defines long-term goals and then maps backward to identify necessary preconditions.
"Theory of Change explains the process of change by outlining causal linkages in an initiative, i.e., its shorter-term, intermediate, and longer-term outcomes. The identified changes are mapped – as the "outcomes pathway" – showing each outcome in logical relationship to all the others, as well as chronological flow. The links between outcomes are explained by "rationales" or statements of why one outcome is thought to be a prerequisite for another.
"The innovation of Theory of Change lies (1) in making the distinction between desired and actual outcomes and (2) in requiring stakeholders to model their desired outcomes before they decide on forms of intervention to achieve those outcomes.
"Theory of Change can begin at any stage of an initiative, depending on the intended use. A theory developed at the outset is best at informing the planning of an initiative. Having worked out a change model, practitioners can make more informed decisions about strategy and tactics. As monitoring and evaluation data become available, stakeholders can periodically refine the Theory of Change as the evidence indicates.
"A Theory of Change can be developed retrospectively by reading program documents, talking to stakeholders, and analyzing data. This is often done during evaluations reflecting what has worked or not in order to understand the past and plan for the future.