Abstract
At the beginning of the 1950s, two Atlantic institutions, the Organisation for European Economic Co-operation (OEEC) and the North Atlantic Treaty Organisation (NATO), converged and nearly merged over the issues of economic co-operation and rearmament. This article seeks to explore this process ›inside-out‹, from the perspective of the international officials and diplomats who executed it. It demonstrates how the OEEC Secretariat, under the leadership of Secretary-General Robert Marjolin, managed to prevent the organisation from being absorbed by the military alliance; and, in turn, infused the NATO Secretariat with its bureaucratic procedures and economic competences.