Uporedno-pravna rešenja podstiču arbitražno rešavanje sporova u oblasti sporta, a pravila mnogih međunarodnih sportskih saveza zabranjuju članicama da vode sudske sporove pod pretnjom zabrane nastupa na međunarodnim takmičenjima. Najznačajniji i najpopularniji arbitražni sud za razrešavanje međunarodnih sporova u domenu sporta jeste Arbitražni sud za sport Lozani (The Court of Arbitration for Sport – CAS) sa sedištem u Lozani (Švajcarska). Da bi CAS bio nadležan za rešavanje određenog spora, on mora biti podoban za arbitražu i mora postojati punovažan arbitražni sporazum. Osim toga, za punovažnost odluka CAS-a važe isti procesni zahtevi kao i za odluke državnih sudova: nezavisnost suda, pravo stranke da bude saslušana, pravo na pošteno suđenje, zabrana retroaktivnih pravila i kazni, načelo ne bis in idem, načelo proporcionalnosti u odmeravanju kazne, načelo nezavisnosti sudije, načelo pisanog obrazloženja odluke. Autor u radu razmatra pitanje punovažnosti i obaveznosti odluka koje donosi CAS i mogućnosti njihovog osporavanja pred nacionalnim sudovima, kako nacionalnim sudovima prema sedištu CAS-a tako i nacionalnim sudovima strana u sportu (u postupku izvršenja odluka CAS-a ili nezavisno od toga). Ovo pitanje je posebno razmotreno u svetlu tzv. slučaja Pechstein (tužba Claudie Pechstein protiv International Skating Union za naknadu štete zbog dvogodišnje zabrane takmičenja usled dopinga) koji je svoj epilog dobio presudom nemačkog Vrhovnog saveznog suda (Bundesgerichtshof) od 7. juna 2016. godine, a ticao se upravo punovažnosti arbitražnog sporazuma o nadležnosti CAS-a i priznavanja odluke CAS-a, kao strane arbitražne odluke, od nemačkih sudova. Comparative law solutions encourage resolving disputes in the area of sport through arbitration, and instigation of court proceedings is forbidden by the rules of many national sport associations under the sanction of barring the athlete from international competing. The most important and most popular arbitration court for resolving the international disputes in the area of sport is the Court of Arbitration for Sport – CAS based in Lausanne (Switzerland). Jurisdiction will be given to the CAS if it is competent for arbitration and if there is valid arbitration agreement. Furthermore, same procedural demands apply to the CAS decisions as for the ruling of national courts: judicial independence, the right of the party to a hearing, the right to a fair trial, forbidding ex post facto laws and sanctions, principle ne bis in idem, principle of proportionality of punishment, principle of a judge impartiality, principle of reasoning behind the decision made in writing. In his paper, the author considers the issue of validity and enforceability of the decisions made by the CAS, and possibility of their denial in front of national courts according to headquarters of the CAS, as well as national courts of the parties to a dispute (in the proceedings of enforcement of the CAS decisions or regardless of that). This issue is particularly considered in the light of so-called Pechsteins case (complaint of Claudia Pechstein against the International Skating Union requesting compensation for receiving two-year ban from competition because of doping results) which was resolved by the ruling of the German Federal Court (Bundesgerichtshof) from 07th June, 2016, and where it was dealt exactly with validity of the arbitration agreement on the CAS jurisdiction and recognition of the CAS ruling as a foreign arbitration decision by the German national courts.