Abstract: There is described an acetabular cup having an outer shell and an inner liner, which inner liner provides a bearing surface of metallic or ceramic material, wherein there is provided in a position around the rim of the inner liner a shoulder formed of a material that is softer than that used for the head or neck of a femoral component with which the acetabular cup is to be used, which shoulder limits the motion of the femoral component during use. The shoulder may be of a polymeric material such as polyethylene. There is also described an acetabular cup having an inner liner of metallic of ceramic material and an outer shell which is manufactured from a bone cement material. There is further described a method of manufacturing the described acetabular cups which method comprises directly molding the polymeric shoulder of outer shell around the ceramic or metallic inner liner.