Early-onset bipolar disorder (BD) is a chronic, recurrent disorder that starts before age 18. In addition to the debilitating effects of BD, which include episodes of lethargic depression and exhausting mania, children and adolescents with BD often have co-occurring disorders, such as attention deficit hyperactivity disorder, conduct disorder, substance abuse disorders, and anxiety disorders. Early interventions may lead to better mental health by preventing BD from ever fully expressing itself. This study will test an early intervention for BD called family-focused treatment (FFT), which targets children and adolescents who are at risk for developing BD. FFT will include education about BD and training in communication strategies and problem-solving skills. It will focus on the family, because family environmental factors are related to the course and recurrence of BD. By reducing risk factors and teaching coping skills, FFT aims to prevent expression of BD, delay the onset or reduce the severity of manic episodes, and ensure that the first treatment received is appropriate.