This study adds to the literature by examining the extent to which school, employment, and romantic relationship factors can disrupt problematic patterns of substance use (i.e. polysubstance use) in a sample of youth followed a decade from adolescence (ages 12-18) to young adulthood (ages 22-29). Specifically, we examine the extent to which school, employment, and romantic relationship factors can disrupt transitions among high-risk use classes at various developmental time points in the transition from adolescence to young adulthood.