Juvenile crime and its immediate and long-term economic and human costs have become a national concern. Programs to prevent and reduce delinquency have developed across the country and one such program in Allegheny County, Pennsylvania (which includes Pittsburgh) is described in this bulletin. The Allegheny program exemplifies a large-scale, comprehensive, and proactive effort to mobilize the community to achieve a collaborative and coordinated anti-violence approach. After two years, system improvements, including increased and coordinated services for juveniles at high risk of engaging in juvenile crime, have led to a corresponding reduction in juvenile crime, including violent crime. The background and the development of the community-wide process is outlined here, including descriptions of specific organizing efforts. Some examples of the accomplishment resulting from this process are offered, as are reasons for success. Also considered is the broad juvenile justice context in which the community effort has taken place. Some of the lessons learned from the program: the need for tact and sensitivity in dealing with the conflicts bound to occur between policymakers and citizens; the importance of experts in providing information. (RJM)