(San Francisco) The short presentations from Frontiers 2013 are all available in video form here. As an enticing example, I present the police chief of Brooklyn Park, MN, Michael Davis. Brooklyn Park is one of the most diverse communities in Minnesota. Chief Davis argues that police forces must move beyond merely engaging their communities; they must help to build communities. He nicely summarizes the work of Harvard sociologist Robert Sampson, which I have described on this blog before. Sampson has shown that, holding other factors constant, neighborhoods with more “collective efficacy” see considerably less violent crime; and networks of nonprofit associations can boost collective efficacy. Chief Davis argues that police can help them do that.