Outcome Mapping is a participatory method for planning, monitoring, and evaluating social change projects. It focuses on changes in the behaviors of those directly engaged by the project, known as boundary partners. The method recognizes that social change is complex, non-linear, and beyond any single actor's control. It aims to encourage iterative learning among partners. Key concepts include distinguishing between a project's sphere of influence and sphere of interest, and defining outcomes as changes in boundary partners' behaviors rather than ultimate impacts of social change.