Although numerous studies reveal differences in mental health by the structure of one's family of origin, there remains debate regarding the processes generating these patterns. Using a sample of young adults (19-21 years) in Miami-Dade County in Florida, this study examines the explanatory significance of three presumed correlates of family type: socioeconomic status, family processes, and level of social stress. Consistent with prior research, our results reveal higher levels of depressive symptoms among those from stepfamilies, single parent families, and single parent families with other relatives present, compared with mother-father families. All three presumed correlates make significant independent contributions to the prediction of depressive symptomatology. Substantial mediating effects also are observed for all three explanatory dimensions. Collectively, they completely or largely explain observed family type variations in mental health risk.