The article focuses on one of the fundamental issues of the functioning of the League of Nations – its mechanism of the use of sanctions. The article is subdivided into two parts. In the first part, which deals with theoretical aspects of the League of Nations’ regime of sanctions, the author has outlined debates about the alternative to war methods of dispute resolution within the League and enforcement of the League’s decisions which finally resulted in the concept of the collective security. Theoretical constructions are illustrated by quotations by leading scientists and some of those high officials who personally participated in the discussion of the issue in question. The author draws attention to some loopholes in the Statute of the League which contributed to the ineffectiveness of the Organization in the sphere of the resolution of those global disputes which were submitted to it. The second part of the article is devoted to the activity of the League in the epoch of international crises such as the Italian invasion to Abyssinia, Japanese aggression against Manchuria etc Inability of the League to constrain aggression on behalf oh the recalcitrant fascist regimes and face connivance of superpowers has given a momentum to the Second World War and led the League to oblivion. The final part of the article contains conclusions and overall estimation of the activity of the Organization.