The proposed Center for Prevention Implementation Methodology (Ce-PIM) for Drug Abuse and Sexual Risk Behavior is designed to accelerate research through the application and integration of system science methods. These system science methods directly model the complex interactions that occur across multiple levels and organizations as prevention programs are implemented. Sophisticated social networking, systems engineering, and computational modeling approaches are used to address the major methodologic gaps that are holding back the movement of science to practice. Aim 1. Integrate and extend system science methods to address critical research challenges of federally funded implementation research aimed at preventing drug use and sexual risk behaviors. This Center uses advanced system science methods characterize, model, and test prevention implementation strategies. Aim 2. Facilitate the seamless integration of methodology into the next generation of prevention implementation research on drug use and sexual risk behavior. This addresses the needs of implementation researchers now in the field, those transitioning from effectiveness to implementation, and those embarking on new careers. Ce-PIM proposes annual conferences, pilot projects, mentoring, and methods development to advance research. Aim 3. Develop a new hybridized form of implementation research by integrating methods within the practice of prevention implementation at the federal, state, county, and local levels. We propose designing field trials to test large-scale implementation strategies as they are "rolled-out" in communities, and designing a range of tools for inexpensive monitoring of the implementation process and decision making. Ce-PIM works with and supports implementation research for 11 qualifying grantees. Its Administrative Core is responsible for Mentoring, Pilot Research Development, and Communication and Dissemination. Its Innovative Implementation Research Methods Core is designed to integrate system science methods and to advance the use of these tools in research and practice.