This Practice Note discusses the World Anti-Doping Agency (WADA) and the World Anti-Doping Code (the Code) 2009, including its purpose and implementation, and the consequences of failing to comply with it. It outlines the rules and policies adopted by sports organisations for banning, and testing for, prohibited substances (drugs), and the procedures for dealing with violations. It also discusses appeals to the Court of Arbitration for Sport (CAS).