The majority of studies addressed in this chapter reflect research findings that provide "best bets" for preventing sexual risk-taking behaviors. These derive from longitudinal, multivariate analyses of reproductive health topics. In addition, a synthesis of programs that have had rigorous experimental designs help provide information on "what works" and what doesn't work within the program field. The synthesis of best bets from research findings, combined from “what works” from those programs that have been evaluated, may help provide a context for the types of programs necessary to help bring levels of adolescent pregnancy, childbearing, and STIs in.