Program theory plays a prominent role in many evaluations, not only in theory-driven evaluations. This paper presents a case study of the process of developing and refining a program's theory within a user-oriented evaluation. In user-oriented (or utilization-focused) evaluations, primary users can play a role in defining their own program theory. This is different, however, from the typical process by which a program theory is developed when using theory-driven evaluation framework. This case study concerns a university's academic outreach program with three local school districts. The program's objective is to increase the number of University of California eligible and specifically University of California, Los Angeles (UCLA) admissible students from targeted local public schools. The authors helped develop and refine outreach staff's program theory. The evaluation procedures are described and results of the theory building process presented. [This article was produced by SAGE Publications, Thousand Oaks, CA.]