In this chapter we examine the importance of program quality and its relationship to outcomes. Included is a discussion what can go wrong when implementing evidence-based programming, the importance of organizational culture and leadership, staff supervision, training and coaching, and monitoring program performance. Techniques, recommendations, and examples are provided, as well as a review of performance measures that can be examined as part of the monitoring of program implementation. Examples of what is included in a program assessment as well as the relationship between program integrity and recidivism are provided. Finally, we review why it is so important to measure and study program quality.