Doping has been a feature of sport since its inception. The use of illegal substances is considered unethical and violates the most important rule – fair play. This article deals with the problem of doping at both the evidentiary and procedural levels. The study presents current trends in doping, the process of doping control, the problems that may arise when carrying out controls, the procedure before the competent body, and the dilemmas that may arise when amending the current anti-doping rules. Attention was also drawn to the ongoing dispute between the Sports Arbitration Court of the Polish Olympic Committee and the Polish Anti-Doping Agency, which has arisen as a result of an amendment to the doping legislation governing the appeal procedure against decisions of individual trial bodies.