 When the Treaty of Rome came into effect on 1 January 1958, Chancellor Konrad Adenauer appointed Von der Groeben as the second German member of the first European Commission, along with Walter Hallstein who became the commission president.Responsible for competition policy, Von der Groeben set the foundations of the European antitrust rights, introduced the value added tax system as well as the adjustment of the control systems and the European joint patents.The December 1961 adoption of the European antitrust rights is based on his efforts to unite the French and German systems.