The logic model: A tool for incorporating theory in development and evaluation of programs

The role of program theory in developing, operating and evaluating programs is gaining increased emphasis in recent years. A clear grasp of a program's theory can contribute to the successful performance of many important developmental and evaluative tasks along its life span. Although there is growing recognition of the importance of program theory in the development and evaluation of programs, it should be noted that this is not a simple task. Programs are often complex, comprising many different types of interlinking components. What is needed is a relatively simple instrument that can help the practitioner explicate and present program theory, by guiding and structuring the process. The logic model is such a tool, whose purpose is to describe and articulate program theory. Drawing upon examples from the authors' work with both nonprofit and governmental organizations, this paper presents potential uses of the logic model tool in explicating program theory for a variety of purposes throughout the life span of programs: for assessing the feasibility of proposed programs and their readiness for evaluation, for program development, for developing performance monitoring systems, and for building knowledge.