This Policy Research Brief proposes an organizational framework for understanding the characteristics of Postsecondary Education (PSE) programs for persons with Intellectual and Developmental Disabilities (IDD) and the relationship of those characteristics to outcomes. The adoption of such a taxonomy could increase understanding of the variety of PSE program models for persons with IDD, provide a basis for comparing outcomes across program sites, and provide a framework for future research. Using the taxonomy to cluster programs and identify testable hypotheses will invite researchers to consider new research questions that will lead to improvements in PSE programs, in person-program fit, and in program-institutional fit. As new evidence accumulates, the PSE Taxonomy itself can be modified to reflect the growing state of knowledge about whether and how various PSE programs contribute to improving the lives of persons with IDD. (Contains 3 figures and 1 table.)