More and more the Nation's police have come to be viewed as the central component in efforts to control crime and urban decay. This Research Preview reports on an 1993 evaluation of the Drug Market Analysis Program in Jersey City, New Jersey—one of five DMA demonstration—an innovative drug enforcement strategy that focused on "hot spots" of drug activity. This study found consistent and strong effects of the experimental policing strategy on disorder-related emergency calls for service. Further, there was little evidence of displacement of drug activity to areas near the experimental hot spots. The data actually suggest a "diffusion of benefits" around the hot spots as compared with the control locations.