The abuse of alcohol is especially common in people with bipolar disorder. However, very little is known about the pharmacotherapy of people with both bipolar disorder and alcohol abuse/dependence. The purpose of this study is to determine if alcohol use and cravings are decreased with quetiapine add-on therapy compared to placebo and to determine if quetiapine add-on therapy is associated with greater improvement in mood, impulsivity, functioning and decreased alcohol use than placebo.