This guide is intended to be useful to educators in high schools and middle schools, to superintendents and school boards, and to state policymakers in planning and executing dropout prevention strategies. The target audience includes school administrators as well as district-level administrators, seeking to help develop practice and policy alternatives for implementation. The guide includes recommendations and indicates the quality of the evidence that supports these recommendations. Descriptions of some ways each recommendation could be carried out are included but are not intended to indicate the best or most effective way to carry out each recommendation in every circumstance. The process for deriving the recommendations began by collecting and examining research studies that have evaluated the impacts of dropout prevention programs. Reviewers relied on What Works Clearinghouse (WWC) evidence standards to assess the quality of evidence supporting educational programs and practices. The technical quality of each study is rated and placed into one of three categories: (1) Meets Evidence Standards for randomized controlled trials and regression discontinuity studies that provide the strongest evidence of causal validity; (2) Meets Evidence Standards with Reservations for quasi-experimental studies with no design flaws and randomized controlled trials that have problems with randomization, attrition, or disruption; and (3) Does Not Meet Evidence Screens for studies that do not provide strong evidence of causal validity. Following the recommendations and suggestions for carrying out the recommendations, additional information is provided on the research evidence from the WWC-rated evaluations to support the recommendations. Four appendixes are included: (1) Postscript from the Institutes of Education Sciences; (2) About the Authors; (3) Disclosure of Potential Conflicts of Interest; and (4) Technical Information on the Studies. (Contains 8 tables and 119 footnotes.)