Bipolar disorder, also called manic-depressive illness, is a brain disorder that causes dramatic changes in a person's mood and energy. People with bipolar disorder undergo periods of extreme happiness and extreme sadness, known as episodes of mania and depression. Early onset of bipolar disorder poses an especially high health risk to affected individuals. For example, adolescents with bipolar I disorder are at increased risk for hospitalizations, social and academic deterioration, suicide, substance abuse, and nonadherence to medications. Treatment-based research for bipolar adolescents has lagged behind research for adults, particularly in the psychosocial arena. Family-focused treatment (FFT), consisting of psychoeducation about bipolar disorder for the patient and relatives, communication enhancement training, and problem-solving training, has shown promise as an effective psychosocial model. In two previous studies, FFT was found to be a useful addition to bipolar medications in treating adult bipolar I disorder. This study will test the effectiveness of FFT that is centered upon the developmental needs of adolescents with bipolar I disorder.