Painful stiffness of the shoulder is an ill-defined clinical entity that is difficult to assess and delicate to treat. The nomenclature used is broad and includes terms such as frozen shoulder, adhesive capsulitis, focal algodystrophy, stiff shoulder, contracted shoulder, and others. Apart from its idiopathic form, the disease can be initiated by trauma, infection, tumour, radiation, systemic and local metabolic disturbances. Pathoanatomically, the common denominator is an inflammatory vascular proliferation followed by thickening, scarring, and retraction of the joint capsule. The inflammatory process often starts at the rotator interval and may extend to the subacromial space. Clinical diagnosis is based on history and physical examination. Generally the onset of pain precedes the perception of a reduced range of motion by weeks or months. In early stages of the disease, the inflammatory type of pain dominates, i.e., the patient's main complaint ist pain at night. In the later stage, range of motion gradually decreases. Patients do not often complain about reduced motion, probably because of its slow onset. Treatment options are a combination of mobilisation exercises with intra-articular steroids, hydraulic distension of the joint capsule, manipulation under anaesthesia, arthroscopic and/or open arthrolysis. The appropriate choice of protocol is just as important as its correct timing. In the inflammatory phase, aggressive treatment protocols are probably contraindicated. Complications of invasive protocols are rare but deleterious and therefore have to be taken into consideration. New anti-anglogenetic agents may enhance functional results and shorten the rehabilitation phase.