Abstract: Studies examining cognitive dysfunction in bipolar disorder have documented neuropsychologic impairment in some patients. Recollection memory, attention, and visual information processing may be particularly impaired in patients with bipolar illness. Cognitive impairment appears to worsen with illness progression, and may have a significant impact on function. Pharmacotherapy to treat bipolar disorder including lithium, anticonvulsants, antidepressants, and atypical antipsychotics may have varying effects on cognitive functioning. Treatment with atypical antipsychotics has been associated with improvement in various cognitive measures in patients with schizophrenia, and the little data available in patients with bipolar disorder suggest the potential for similar benefits. Studies to determine if current treatments for bipolar disorder can prevent, delay, or even improve cognitive dysfunction are needed.