To better understand the problems associated with diagnosis of bipolar disorder, especially problems related to race and ethnicity, this study compared whites, African Americans, and Latinos with bipolar I disorder in the presentation of manic symptoms, depressive episodes, functional impairments (Short Form-12), and self-reports of schizophrenia diagnosis. Data for this study were derived from the 2001 National Epidemiologic Survey on Alcohol and Related Conditions, which are nationally representative of United States households. African Americans and Latinos expressed similar rates in presentation of 14 out of 16 manic symptoms compared with whites, with the exception of grandiosity/self-esteem, in which they were more likely to exhibit this symptom compared with whites. Higher rates of depressive episodes were observed among whites, and these episodes occurred significantly earlier compared with African Americans and Latinos. Latinos had slightly higher vitality scores on the SF-12 measures after adjusting for sociodemographic and clinical factors, but no other differences across the groups were observed. Overall, these data show that the expression and functional impairments of bipolar I disorder is very similar across racial ethnic groups using this community-based sample. This is the first community-based study making such comparisons, with results suggesting that provider biases are more likely to explain problems in misdiagnosis than fundamental differences in the presentation of bipolar disorder across racial/ethnic groups.