to examine the origins and aftermath of membership in juvenile street gangs, we rely on data from the Rochester Youth Development Study, an ongoing, longitudinal investigation of antisocial behavior. This study, which began in 1986 with funding from the Office of Juvenile Justice and Delinquency Prevention, focused on the causes and correlates of serious, violent, and chronic delinquency. The study of gangs is just one aspect of this broader research initiative, but one that is very central to the core aims of the study. In this chapter we introduce the reader to the design of the Rochester study and describe the study's sample and measures, especially as they focus on issues related to gangs and gang membership.

The Rochester Youth Development Study

The Rochester Youth Development Study follows a panel of juveniles from their early teenage years through their early adult years. Figure 2.1 depicts the overall research design of the study. To date, we have collected 12 waves of data spanning the ages of 13 through 22.

Each subject and a primary caretaker (in the vast majority of cases this is the biological mother) were interviewed at six-month intervals from the spring of 1988 until the spring of 1992. After a two-year gap in data collection, annual interviews began in 1994. By the end of Wave 12 in the spring of 1997, we had reinterviewed 846 of the initial 1,000 subjects in the study, a retention rate of 85%.