Total joint replacement is one of the revolutionary procedures, not only in orthopedics, but in medicine in general. Examples of such a breakthrough so successful in increasing the quality of life of patients are rare. The patient population in need of joint replacement and the proportion of the young patients in this population is constantly increasing. Increased life expectancy brings new challenges for surgeons and prosthesis manufacturers. In the first prosthesis designs mobility was sacrificed in a degree in order to provide stability. Achieving stability by constraining designs caused increased load transfer to bone-implant interface and resulted in component loosening. A balance between implant stiffness and flexibility must be obtained according to patients` needs. The latest implant models may not necessarily be the ideal choice for every patient. There must be a conformity between patients demands and what the implant offers. An ideal prosthesis should provide stability without compromising mobility. The designs of the new materials aim to decrease the friction and wear. Wear particles accumulate in the joint space and pushed into the spaces between the bone and the implant. The foreign body reaction, induced by these particles results in osteolysis and loosening of the implant. New materials with low wear rates and low reactivity are developed to overcome this problem. New porous materials are introduced to enhance bone-implant integration by stimulating bone ingrowth. This section focuses on current component designs and new advances in hip arthroplasty to achieve good a fixation to bone, low wear of bearing surfaces, adequate stability and high range of motion.