Evaluability assessment is a diagnostic and prescriptive technique that can be used to determine the extent to which different problems inhibit program evaluation. It involves policymakers, managers, and staff in developing program theory, clarifying intended uses of evaluation information, and planning further evaluations that would stimulate…

Program theory and implementation process theory contribute, respectively, to specifying the what and the why of program delivery. This article discusses the relationship between these two theories and the types of data collection methods that can be derived from each in order to contribute to more comprehensive evaluation designs. (JAZ)