Cheating by doping has done more than perhaps any other type of misconduct in elite and professional sport to erode public confidence in the credibility of athletic performances and the legitimacy of sporting results. Since the 1980s, a sophisticated and extensive infrastructure has developed to ensure that sport is doping-free. This includes the World Anti-Doping Agency, the World Anti-Doping Code, the Anti-Doping Division of the Court of Arbitration for Sport, national anti-doping agencies, national anti-doping policies, anti-doping education programmes, and, in some countries, even doping-related criminal offences. Imagine a drug that enhanced athletic performance significantly, was cheap to purchase, but presented a substantial risk of permanent harm to, or even the death of, the user. Perhaps the most common argument offered for the prohibition of doping is that performance-enhancing drugs are harmful to athletes. While health is an important aspect of athlete welfare, one might object that another important aspect of athlete welfare is autonomy.