Adult-onset Still's disease is a rare inflammatory systemic disease. Cardinal symptoms/manifestations are fever, arthralgias or arthritis, myalgias, the typical skin rash, sore throat, hepatosplenomegaly, lymphadenopathy and serositis. Several other symptoms and organ involvements are possible. The clinical picture is variable with mild to life-threatening courses. The disease is self-limiting, intermittently active or chronic. Because of the lack of a defined diagnostic test the diagnosis of AOSD can only be made after exclusion of several differential diagnoses in particular of infectious, malignant and autoimmune origin. For therapy non-steroidal anti-inflammatory drugs, glucocorticoids, disease modifying antirheumatic drugs and biologics can be used.