 He ranks among the fathers of the European Union, he was one of the authors of the Spaak Report, calling for the establishment of the European Economic Community.He was vice-chair of the German delegation, led by Alfred Mueller Armack at the 1956 Brussels Conference which led to the Treaty of Rome and was chair of the "Common Market" committee.He is responsible for the fact that the EEC received a contractually specified free market framework and found a kindred spirit in the French delegation leader, Robert Marjolin.