Primary shoulder stiffness is idiopathic. Due to coincidence with other diseases, a systemic genesis with hormonal influence is discussed. The result of chronic inflammation with fibroblastic proliferation is a fibrotic capsule, atrophy of ligaments, and muscular dysbalance. The main symptom is painful restricted passive and active shoulder motion. There is a high rate of unsatisfactory courses. Therapy depends on the phase and duration of shoulder stiffness. Primary treatment of choice is oral steroid therapy, followed by physical and physiotherapy. Steroids can be applied intraarticular, as an alternative. If conservative treatment fails after a period of 6 months, arthroscopic arthrolysis is indicated. Secondary shoulder stiffness often results from traumatization or operation of the shoulder. Primary treatment is also conservative, but operative intervention should be performed early after unsuccessful therapy. Intensive, passive mobilization is necessary after arthrolysis.