This paper explores the relationship between changes in HIV risk behaviors and physical and sexual abuse. A stratified random sampling procedure selected 602 youths from a sample of 2,787 patients seen consecutively at public health clinics in 10 cities. Face-to-face structured interviews conducted since 1984-85 provide a history of change in risk behavior from adolescence to young adulthood. Univariate and bivariate analyses assessed differences in demographic and number and type of risk behaviors between those experiencing single or multiple types of abuse and those with no abuse history at all. The results show that a history of physical abuse, sexual abuse, or rape is related to engaging in a variety of HIV risk behaviors and to a continuation or increase in the total number of these behaviors between adolescence and young adulthood. This information might help practitioners to both prevent initial involvement in HIV risk behaviors and to prevent continuation of behaviors as youths move into young adulthood.