Creatine has been known as a constituent of food for over 150 years having been discovered in 1832 by Chevreul who extracted it from meat. However, although phosphocreatine and its role in exercise was established in 1927, it was not until the early 1990s that significant levels of research were undertaken examining the effects of creatine supplementation on sports performance. This chapter briefly examines the synthesis and breakdown of creatine before considering its metabolic role in energy production within cells. Sections on the effectiveness on creatine loading regimens are also dealt with, as are explorations of enhanced muscle creatine on performance. Final sections relate to the health aspects and clinical implications of creatine supplementation.