During recent years valproate has been established as a cornerstone for the drug-treatment of bipolar disorder. In Germany, valproate was licensed both for the treatment of acute mania and for maintenance treatment in summer 2005. At this occasion, this review summarises the scientific evidence and clinical experience of well-known experts with valproate-treatment. It was concluded that valproate will continue to be of high clinical significance despite the recent increase of treatment alternatives, both in monotherapy and combination treatment of acute mania, mixed states and maintenance treatment.