This is the first controlled acute treatment study of bipolar disorder in adults 60 years or older with current DSM-IV manic, mixed, or hypomanic episodes. The number of older adults with severe and disabling bipolar disorder is increasing, and information to guide the management of the treatment of the disease is lacking in this population. Guidelines for treatment of younger people with bipolar disorder cannot be used for older people, and there are no safety and efficacy data upon which to base initial treatment decisions for older patients with bipolar mania. Mood stabilizers (lithium and divalproex) are the first-line treatment for bipolar disorder. However, in aged patients physiological changes and comorbid diseases may increase vulnerability to side effects and limit the benefits of the medications.