Carbamazepine has a long history in psychiatry and neurology. More recently, carbamazepine extended-release capsules have been approved by the US Food and Drug Administration for the treatment of manic and mixed episodes associated with bipolar I disorder. This decision represents a significant step forward for the agent, which was first described to have efficacy in the disorder in the early 1970s. Approval of carbamazepine extended-release capsules was aided by two large placebo-controlled, 3-week trials. Using nearly identical protocols, these trials demonstrated that monotherapy with carbamazepine extended-release capsules was effective for the treatment of acute mania in patients with bipolar I disorder. Recent data collected based on this new formulation of carbamazepine illustrate the need for education about the utility of this compound in bipolar disorder.