The Standardized Program Evaluation Protocol (SPEP) is a system that rates the potential for therapeutic services to reduce recidivism among youth, by comparing programs to what prior evaluation has shown to be effective. SPEP ratings are intended to guide program improvements in a cycle of Continuous Quality Improvement. This report describes the general requirements and drivers of successful implementation of the SPEP, as informed by implementation at three sites participating in the Office of Juvenile Justice and Delinquency Prevention’s Juvenile Justice Reinvestment and Reform Initiative. Trying to implement the SPEP often uncovers deficiencies in risk assessment systems, client tracking systems, and/or quality assurance systems that feed into SPEP ratings. As a result, implementing the SPEP typically takes two to three years, during which the SPEP can serve as a useful vehicle to motivate system improvements.