Instability is a major cause of failure in total hip arthroplasty. Large femoral heads have been introduced to improve stability. Although this has been effective in reducing dislocations, optimal component position is still required to maintain stability. In addition, large head articulations have introduced new potential problems, including wear, polyethylene fracture, and taper corrosion. In order to be clinically beneficial, the use of large femoral heads must be complemented with optimal component position and balanced against any potential risks.