Objectives-This study examined early psychosocial precursors (internalizing behaviors and parent-child bonding) of adult tobacco use, alcohol, and other drug-related problems and later adverse health consequences.Methods-A community-based sample of 502 participants were interviewed over a 22-year period (1983, 1985-1986, 1997, 2002, and 2005).Results-There is a strong relationship between later adolescent internalizing behaviors and later adverse health consequences in adulthood. Later adolescent internalizing behaviors serves as a mediator between low parent-child bonding in earlier adolescence and later adverse health consequences. Tobacco use, alcohol, and other drug-related problems in the late 20s and early 30s are directly related to later adverse health consequences and indirectly as mediators between earlier psychosocial difficulties and later adverse health consequences.Conclusions-Public health and clinical implications suggest the importance of creating policies and programs and providing treatment that target parent-child bonding and internalizing behaviors in order to reduce tobacco use, alcohol, and other drug-related problems, and ultimately, later health problems.