This article discusses the evaluation of programmatic interventions to enhance postsecondary STEM education for students with disabilities. SciTrain University, a federally funded project to provide instructor training on accessible teaching according to universal design principles, is presented here as a case study on evaluation for similar programs. This article highlights the evaluation process, including relevant evaluation questions and selection of indicators, use of a mixed-methods approach, and development of instruments. We give particular attention to the utilization of longitudinal participants in order to document the project's effectiveness. Project evaluators used demographic and performance data, classroom observations, and online journals to determine the efficacy of the training provided to these longitudinal participants. For these three activities, we discuss the development and deployment of instruments and offer some preliminary findings. Finally, the article concludes with a brief discussion of internal project assessment and its role in project refinement. Given a dearth of scholarship on the evaluation of programs to enhance STEM education for students with disabilities, this article seeks to provide some practical insights into the potential for mixed-methods approaches. (Contains 2 tables and 6 figures.)