The document contains: (1) An Update on Adolescent Risk-Taking, including why it is both necessary and an opportune time to improve and expand the network of effective prevention programs; (2) The Common Elements of Successful Prevention Programs, briefly summarized, along with an explanation of the criteria used to select the 51 programs profiled in this guidebook; (3) Moving from Research to Practice, including challenges to replicating promising prevention approaches and suggested ways to meet those challenges; (4) A Prevention Readiness Questionnaire to help program directors and planners; (5) Profiles of 51 Prevention Programs, including general information, unique features, evaluation results and general contact information. The 21 most rigorously evaluated programs also include curriculum, training and contact information; and (6) A Handy Reference Chart for quick comparison of the 51 programs. Tables, figure, index, references