The authors characterized concurrent psychiatric diagnoses among patients with a diagnosis of bipolar disorder who were in routine care by using administrative data from a Department of Veterans Affairs facility. Of 813 patients who had a diagnosis of bipolar disorder in 2000, 21 percent were older (>/=60 years) whites, and 2 percent were older African Americans. Older African Americans were the most likely to have a diagnosis of schizophrenia documented in the medical record compared with younger African Americans, older whites, and younger whites (67 percent, 34 percent, 38 percent, and 27 percent, respectively). The results suggest that older African-American patients with bipolar disorder are more likely to receive diagnoses of mutually exclusive conditions, such as schizophrenia, and thus appear to have an elevated risk of their illness being underrecognized or misdiagnosed and receiving inappropriate treatment.