Aripiprazole is now well recognized for its capacity to potentiate antidepressants in the treatment of unipolar depression. However, two randomized controlled trials of aripiprazole in the treatment of bipolar depression were negative. This surprising result may stem from the fact that the doses of aripiprazole used in these studies were rather high (17.6 ± 8.3 mg/d in study 1 and 15.5 ± 7.5 mg/d in study 2) and could have contributed to inhibit dopaminergic activity in key brain areas involved in the modulation of rewards, motivation and concentration. Bipolar depression is indeed heavily loaded with general symptoms of psychomotor retardation including poor concentration, low energy level, hypersomnolence, and hyperphagia. All these functions are modulated by dopamine and strategies aimed at improving dopaminergic function are used frequently to resolve residual symptoms of bipolar depression.