Synovial disorders and loose bodies are one of the most common indications for hip arthroscopy. Arthroscopic intervention has been reported for loose bodies, synovial plicae, synovial chondromatosis, pigmented villonodular synovitis (PVNS) as well as rheumatoid and septic arthritis. One major advantage in comparison to radiologic imaging is the ability to inspect, biopsy, and treat within one procedure. In contrast to an arthrotomy, hip arthroscopy avoids the potential risks of extensive surgical exposure and prolonged rehabilitation. Nevertheless, hip arthroscopy cannot be promoted as curative in all synovial disorders. In patients with loose bodies, synovial plicae, initial septic arthritis and, to a certain extent, PVNS curative therapy and "restitutio ad integrum" can be achieved. In contrast, in patients with synovial chondromatosis and rheumatoid arthritis, the goal of hip arthroscopy is to enable the correct diagnosis and to provide symptomatic relief and maintain or improve joint function. Success or failure of arthroscopic treatment depends on proper patient selection and a correct arthroscopic technique.