Shoulder joint infections are severe pathological conditions. Since the success of therapy is decisively dependent on early treatment, if joint infection is suspected, the patient should be hospitalized immediately. Characteristic suspicious features are extremely severe shoulder pain, adoption of a pain-relieving posture, and severe malaise. The diagnosis and differential diagnosis are discussed. In addition to selective parenteral administration of antibiotics, treatment comprises various methods of draining the shoulder joint in combination with temporary immobilization.