This study investigated the impact of parental alcoholism and various indices of family functioning on differentiation levels of young adults. A total of 813 college students completed the Differentiation of Self Inventory (DSI; Skowron & Friedlander, 1998 Skowron, E. A. and Friedlander, M. L. 1998. The Differentiation of Self Inventory: Development and initial validation.. Journal of Counseling Psychology, 45: 1–11. [Crossref] , [Google Scholar]), the Self-Report Family Inventory Version II (SFI; Beavers & Hampson, 1990 Beavers, W. R. and Hampson, R. B. 1990. Successful families, New York: Norton.  [Google Scholar]), and questions related to experiences in their families of origin. Analyses indicated that parental alcoholism and levels of functioning, as well as certain experiences within alcoholic families, are significantly predictive of differentiation levels of adult children. Clinical implications of the findings are discussed.