The management of skeletal metastases can be challenging for the orthopaedic surgeon. They represent a significant source of pain and disability for cancer patients, adding to the morbidity of their condition. Treatment is directed at the alleviation of symptoms and the restoration of function. Metastatic involvement of the proximal humerus can be especially debilitating, having the potential to cause severe pain which leads to loss of function, and may also be complicated by pathological fracture and hence attenuate upper limb function. We present a report of four cases where the use of reverse geometry proximal shoulder prostheses has provided excellent symptomatic relief and a pain free functional range of movement in metastatic proximal humerus disease. To demonstrate a novel, effective surgical strategy for the management of proximal humeral metastatic disease in elderly patients with concomitant poor rotator cuff function, a review of the medical records and radiographic imaging who underwent reverse geometry shoulder replacement for metastatic disease of the proximal humerus was performed. Two cases were secondary to breast cancer, the other two of unknown primary. All four patients were referred with severe shoulder pain significantly limiting range of movement, in one case pathological fracture was demonstrated. In all cases significant symptomatic relief was achieved in the post operative phase, signified by a marked reduction in analgesic requirements. Two patients were completely pain-free at follow up, whilst the remaining two used only minimal oral analgesia. Upper limb function was preserved in all cases, with demonstration of a satisfactory range of motion adequate for activities of daily living in all patients. No surgical complications were noted. The use of reverse geometry shoulder prostheses in proximal humeral metastases (either with or without an associated proximal humeral fracture) demonstrates a reliable and effective method of pain relief with excellent restoration of upper limb function. The unique implant geometry allows the patient to achieve a functional range of motion without reliance on the rotator cuff musculature, which is often defunct in elderly patient groups.