We describe lifetime rates of club drug use among 782 youths in treatment for substance abuse. Rates (%) for youths under eighteen (N = 486) were methylenedioxymethamphetamine (MDMA), 32.3; gamma-hydroxybutyrate (GHB), 7.0; lysergic acid diethylamide (LSD), 48.6; ketamine, 18.3; and methamphetamine, 30.2. For youths 18-32 (N = 289) rates (%) were MDMA, 37.0; GHB, 13.1; LSD, 42.9; ketamine, 17.0; and methamphetamine, 31.5. Older youths reported significantly more use of GHB than younger youths (p < .01). Youths reported using club drugs frequently outside of rave settings. Club drug use is common among youths in treatment for substance abuse and has spread beyond the rave culture.