This article employs a prosopographical approach in examining the backgrounds and careers of those cadres who represented the Communist Party of Great Britain and the Parti Communiste Français at the Comintern headquarters in Moscow. In the context of the differences between the two parties, it discusses the factors which qualified activists for appointment, how they handled their role, and whether their service in Moscow was an element in future advancement. It traces the bureaucratization of the function, and challenges the view that these representatives could exert significant influence on Comintern policy. Within this boundary the fact that the French representatives exercised greater independence lends support, in the context of centre–periphery debates, to the judgement that within the Comintern the CPGB was a relatively conformist party.