This article briefly presents the complexity of the issue of partiality in arbitration. It is a phenomenon which is complicated in national as well as international arbitration proceedings since one may not escape the impression that connections between arbitrators and legal representatives of parties are more and more obvious, and what was once considered a ground for exclusion is now common practice. Yet there are deceitful efforts of parties to arbitration to exclude arbitrators, which negatively affect the efficiency of arbitration. It is necessary to maintain cooperation between arbitrators and general jurisdiction courts.