The World Anti-Doping Code was first adopted in 2003 and took effect in 2004. It was subsequently amended four times, the first time effective 1 January 2009, the second time effective 1 January 2015, the third time effective 1 April 2018 (compliance amendments) and the fourth time effective 1 June 2019 (reporting of certain endogenous substances as Atypical Findings).
The revised 2021 World Anti-Doping Code is effective as of 1 January 2021.