Data were obtained from interviews conducted between 1998 and 2000 as part of an ongoing South Florida study of risk and protective factors associated with young adult substance use and mental health problems. The initial sampling pool for the study was composed of a representative sample of 5,370 boys and 554 girls previously studied during early adolescence. A stratified random sample was drawn that roughly conformed to the ethnic and racial composition of the Dade County school system. Overall, 76.4 percent of those who were chosen and recruited for the study were successfully interviewed, including 911 boys and 319 girls. The data collected from the 1998 to 2000 interviews were gathered when the respondents were between the ages of 18 and 23 years. These data were supplemented with data collected when the respondents were in either the eighth or ninth grade (wave 3 of the adolescent study conducted in 1993). Those young adults interviewed from 1998 to 2000 were compared with the total sample drawn from the original adolescent study population on a wide array of early adolescent behaviors and family characteristics of possible relevance to mental health or substance abuse risk. The study findings indicated that recent exposure to violence in the community, along with a history of receiving traumatic news, direct victimizations in the community, recent life events, and associations with criminal peers increased the risk for young adult criminal offending. 3 tables, 6 notes, and 58 references