The use of multilateral institutions to promote and defend democracy is one of the most remarkable recent trends in politics. The novelty of the approach has generated enormous interest among social-science scholars, yet none of the major studies on the subject explores the origins, nature, and performance of the mutilateralization of democracy promotion and defense in Africa. This article seeks to fill this gap by examining how the African Union promotes and defends democracy in Africa. Examination shows that the record is mixed: the African Union has dealt decisively with coup-makers, but it has been far less successful in dealing with democratic backsliding. Despite the diplomatic toolkit at its disposal, its record at preventing misrule is at best questionable.