2. Subjects with a current diagnosis of bipolar I disorder, as defined by DSM-IV-TR criteria and confirmed by the MINI and a history of at least one previous manic or mixed episode with manic symptoms of sufficient severity to require one of the following interventions: hospitalization and/or treatment with a mood stabilizer, and/or treatment with an antipsychotic agent, in addition to their current manic episode. "Require" is defined as an intervention that occurred rather than one that was recommended. Rapid cyclers with 8 or fewer episodes in the previous year will be included.