Intervention programs are open systems that must withstand the disturbances of the environments in which they are implemented if they are to thrive. Stakeholders can benefit from proactive insights related to potential program malfunction or failure. Evaluators have not developed approaches to serve this preventive function. This study proposes the program stress test as a holistic, preventive approach to program evaluation, aiming to identify vulnerable areas at risk of failure, and to suggest preventive strategies. The stress test can be used in the planning stage of a program (called ex-ante stress test), or during the implementation stage (called ex-post stress test). This study illustrates an ex-post test. The authors introduce its concept, methodology, research steps, and application to a student retention program, including findings of structural and functional issues, as well as solutions proposed by participants. The authors call the evaluators' attention to the need to expand the traditional scope of evaluation, to include future-focused assessments.