This paper reports the results of two randomized field experiments, each offering different populations of youth a supported summer job in Chicago. In both experiments, the program dramatically reduces violent-crime arrests, even after the summer. It does so without improving employment,...

Most randomized controlled trials (RCT) of social programs test interventions at modest scale. While the hope is that promising programs will be scaled up, we have few successful examples of this scale-up process in practice. Ideally we would like to know which programs will work at large scale...