A humeral component (2) of a reverse shoulder prosthesis comprises an elongatestem part (4) for location within the intramedullary cavity of the humerus,and an epiphyseal part (8) having a concave bearing surface (12) forarticulation with the convex bearing surface of a glenoid component . Theelongate stem part (4) defines a stem axis and the concave bearing surface(12) of the epiphyseal part defines an epiphyseal axis. The epiphyseal axis isoffset posteriorly relative to the stem axis.