Chris Blattman writes in the Washington Post about his study, co-authored with Margaret Sheridan, Julian Jamison, & Sebastian Chaskel, and conducted with IPA Liberia. The study evaluated the Sustainable Transformation of Youth in Liberia program, which provided cognitive behavioral therapy (to which the researchers also added cash grants) to young men at risk of violence and crime. Professor Blattman reflects on the origins of the study, and the implications of the 10-year follow-up which showed sustained reduction in crime for the young men who went through the program.