OBJECTIVE: Psychopharmacological treatment of bipolar disorder is quite complex because of its clinical features of different episodes and various course. We published Korean Medication Algorithm Project for Bipolar Disorder (KMAP-BP) in 2002, that appeared to be helpful in clinical situation by feasibility study in 2005, and revised KMAP-BP in 2006. New papers in which some drugs are effective in treating bipolar disorder have been published, and the demand for revision of KMAP-BP are increased. METHODS: The questionnaire was sent to 94 experts, 65 of whom replied. It was composed of 40 questions about clinical situations, and each question includes various sub-items. Based on KMAP-BP 2006 and new data, some questions sub-items are amended. Safety issues and consideration on special populations were added in this revision. Each option was categorized on three parts (the first-line, the second-line, or the third-line) by its 95% confidence interval. RESULTS: In acute manic episode, even though it is euphoric, mixed, or psychotic, combination of a mood stabilizer (MS) with an atypical antipsychotic (AAP) is recommended as first-line strategy. Mood stabilizer monotherapy is first-line in hypomanic episode. Among the mood stabilizers, valproic acid and lithium are selected as first-line. Monotherapy with mood stabilizer is recommended in mild to moderate bipolar depression. However, triple combination of a mood stabilizer, an atypical antipsychotic and an antidepressant (AD), is the first-line strategy in non-psychotic severe depression. Also combination of MS and AAP (MS+AAP) and combination of MS and AD (MS+AD) are recommended as first-line. In psychotic bipolar depression, combination of MS, AAP, and AD (MS+AAP+AD), combination of MS and AAP (MS+AAP), and combination of AAP and AD (AAP+AD) are first-line strategies. In bipolar depression, lithium, lamotrigine, and valproic acid are selected as first-line mood stabilizer, and quetiapine, olanzapine and aripiprazole are preferred antipsychotics. Bupropion and (es)citalopram are first-line antidepressant in moderated depression, and (es)citalopram, bupropion, and paroxetine are recommended as firstline in severe depression. Preferred strategy for rapid cycling patients is combination of MS with AAP. In maintenance treatment, combination of MS with AAP and monotherapy of MS are recommended as first-line. CONCLUSION: In treating bipolar disorder, even the first step of treatment, consensus of experts are changed from our studies in 2002 and 2006. This medication algorithm, with some limitations, may reflect the clinical practice and recent researches.