An acetabular cup comprises an outer shell preferably having a first tensile modulus, an inner liner preferably having at least a second tensile modulus which is greater than that of the said first tensile modulus, and at least one reinforcing element which extends from a polar region of the outer shell along a, preferably interior, surface of the outer shell. Preferably, a wall thickness of the outer shell at a region of intersection between a part-spherical portion and a frusto-conical portion of the outer shell is less at the part-spherical portion than at the frusto-conical portion. The reinforcing element has a longitudinal extent which improves the rigidity of the wall at at least the part-spherical portion.
