摘要: Before we could carry out systematic studies and intervention projects on the active heroin addict population of our community, were in need a field concept that would define addicts as members social system rather than individual units. Early observations suggested most users an urban community are already natural group structure, ie, they participate daily operations neighborhood heroin-distribution system. To explore possibility organizing epidemiologic activities around this drug-distribution system, team was assigned to intensive study one such copping area. The observed gathered information from all who regularly obtained or distributed at site for period six months. This experience suggests it is possible obtain data frequent area, might be impact treatment, other competing factors prevalence use sites.