Adult-onset Still’s disease (AOSD) is an inflammatory systemic disease of unknown aetiology, this may occur in any age in the adult and is associated with a diverse array of clinical symptoms. Typical symptoms of the disease are fever, arthralgias or arthritis, myalgias, the typical skin rash, sore throat, hepatosplenomegaly, lymphadenopathy and serositis. Characteristic laboratory abnormalities are elevated parameters of systemic inflammation, elevated liver enzymes, leukocytosis with predominant neutrophilia, anaemia and, in particular hyperferritinaemia. Typically the disease starts with systemic manifestations. The course of the disease can be self-limiting, intermittently active or chronic. If chronic, a destructive arthritis may often occur. Although the overall prognosis is favourable, severe and even life-threatening courses can develop. Because of the lack of a specific diagnostic test, the diagnosis of AOSD is based on clinical parameters after an exclusion of several differential diagnoses, in particular of infectious, malignant and autoimmune origin. In the acute disease non-steroidal anti-inflammatory drugs and systemically employed steroids are used for therapy. If they fail to induce sufficient control of disease activity, other drugs commonly used in the treatment of inflammatory diseases, such as DMARDs, in particular methotrexate, are used. In the past years, new therapeutic strategies for patients resistant to conventional therapy have successfully been employed with biologics, such as TNF-blockers and anakinra.