Total hip replacement was successfully introduced in November 1962 in England by the late Sir John Charnley with the expressed intention of relieving the pain and suffering of those afflicted with severe osteoarthritis of the hip joint. A significant amount of engineering and bio-engineering work went into the production of the final articulating surfaces of metal on high molecular weight polyethylene. This was meant to simulate the low coefficient of friction in normal articular joints. It was not long before this innovation spread throughout the world and, today, most joints can be replaced by artificial equivalents. Over the five decades since its introduction, there have been changes in designs of implants with the use now of additional bearing surfaces, for example, metal on metal, ceramic on polyethylene and ceramic on ceramic. Joint replacement has been heralded as one of the greatest orthopaedic innovation of the 20th century. Initially more hip than knee replacements were done; however, that trend has been reversed in most parts of the world.