This issue of the Psychiatric Clinics edited by Dr. John Beyer is dedicated to the topic of Bipolar Depression, from the genetics of the disorder, to the therapeutic options, to treatment in special populations. Articles in this issue include, but are not limited to: Differences in Bipolar and Unipolar Depression, Suicide and Bipolar Disorder, Social Relationships, Support, and Life Events in Bipolar Disorder, Treatment of Bipolar Depression in Pregnancy and the Post-Partum Period, Psychotherapy for Bipolar Depression, Cognition, Dementia, and Bipolar Depression, and Genetics of Bipolar Disorder.