The issue of doping is always a very interesting topic in the modern sport. Doping is also interesting not just for medicine and biomedicine but for the law point of view. This paper firstly defines doping and gives a review of the legal framework (national and international). In the end, just to show how the issue of doping is complex, it discusses three cases decided before the Court of Arbitration for Sport (CAS): the Strahija case, the Ademi case and the Dobud case.