Bipolar disorder is a severe and often chronic disorder with lifetime prevalence rates of bipolar spectrum disorders of up to 6.5% in the general population. Patients with bipolar disorder frequently report co-occurring substance use disorders, and the rates of alcohol and other substance use disorders are significantly higher in persons with bipolar disorder than in the general population. The present review discusses why people with bipolar disorder use substances, provides an overview of the impact of alcohol and other substance use on the course of bipolar disorder, and outlines the treatment options currently available to patients with co-occurring bipolar disorder and substance abuse. Our aim is to summarize the existing data on the pharmacologic treatment options and to include the most recent published data whenever possible. Three randomized, placebo-controlled studies of dual-diagnosis patients treated with carbamazepine, lithium, and valproate are discussed. The results are generally positive and support the use of these agents in dual-diagnosis patients. Open-label studies are also presented, and the need for controlled data is outlined. The review also briefly discusses the psychotherapeutic approaches to patients with comorbid bipolar and substance use disorders.