 This study aims to test the preliminary efficacy of 3.0 mg of guanfacine GFC daily versus placebo in cocaine andor alcohol dependent individuals. This proposal is a laboratory and treatment outcome study to examine the effects of guanfacine on brief exposure to stress, drug cues and neutral situations on cocainealcohol craving, mood and neurobiological reactivity in a sample of cocaine andor alcohol dependent individuals. Guanfacine will be beneficial for reduction in stress and drug cue induced craving and related arousal. In a sample of 60 cocaine andor alcohol dependent men and women, we propose to examine a differences in measures of cocaine craving, emotion state, hypothalamic-pituitary-adrenal HPA activation, physiological arousal and plasma catecholamine response to stress imagery and to drug cue imagery as compared to neutral imagery; b reduction in cocainealcohol abstinence symptoms; and c improvement in cocaine and alcohol treatment outcomes as measured by increasing abstinence, reduction in cocainealcohol use and increased treatment attendance. Hypothesis 1: Guanfacine will decrease stress-induced cocaine craving, negative emotions and related arousal in the laboratory as compared to placebo. Hypothesis 2a: As compared to the PLA group, the GFC group will show significant reductions in protracted withdrawal symptoms as measured by the CSSACIWA during the 9-week treatment period. 