This double-blind study will compare the benefits and side-effects of 9 weeks of treatment with lithium and divalproex in people with bipolar mania. Participants, who may be treated during inpatient hospitalization or as outpatients, will be randomly assigned to receive either lithium or divalproex. During the first 3 weeks of treatment careful titration of lithium and divalproex will be done to reach dose ranges. All other psychotropic medications will be discontinued. Behavioral interventions and/or lorazepam may be added, if necessary. After the first 3 weeks, if symptoms do not improve, risperidone will be added to be taken everyday with the study medication.