Background: Over the past decade, a variety of psychosocial interventions have been reported to be beneficial for bipolar disorder. Acceptance of this literature has been slow in part because most studies have been small and lack rigorous methodology. Furthermore, skepticism about the potential efficacy of psychosocial treatments stems from recognition of the indisputable biological basis of the disorder. Well powered randomized trials are the standard by which pharmacologic strategies demonstrate efficacy. Thus, we review the randomized controlled trials of psychosocial interventions as an adjunct to medication in the treatment of bipolar disorder. Methods: We conducted a literature search to identify randomized controlled studies of Cognitive-Behavioral therapy (CBT), Psychoeducation (PE), Family-Focused Therapy (FFT), and interpersonal social rhythm therapy (IPSRT) for bipolar disorder. Only studies which randomized at least 80 individuals diagnosed with bipolar disorder were selected for review. Results: Nine studies met our inclusion criteria and of these, eight found that adding one of the above psychosocial interventions to pharmacotherapy improved treatment outcomes for individuals with bipolar disorder. None of the psychosocial interventions claims benefit for acute treatment of hypomania or mania; however, CBT, FFT, and IPSRT appear efficacious in treating depressive symptoms and preventing new episodes. PE appears helpful against the recurrence of hypomania or mania, but not depression. Conclusions: These findings support the use of psychosocial interventions in treating individuals with bipolar disorder.