• Legal and EU Policy Counsel of the Christian Democratic Party's Vice-Chairman at the German Federal Parliament (Bundestag) and at the Länder-Parliament of Northrhine-Westphalia (Landtag) 
  • International Affairs Official of the German Chamber of Auditors (i.e. German equivalent of Chartered Accountants) with responsibilities concerning EU, FASB, IASB, GATS, WTO related legislation and bilateral relations with other EU- and Non-EU-countries
  • Head of the Regional Office of the German Chamber of Auditors for the 5 Northern Länder of Germany
  • Team Leader and Lead Legal Expert of legal approximation and harmonisation projects of the European Commission in EU candidate countries and association countries (i.e. Baltics, Eastern Europe, Balkans, Malta, Turkey) in cooperation with KPMG, Berenschot International/NL, IBF/B, German Foundation for International Legal Cooperation/GER, ICON/GER, Human Dynamics/A
  • Partner of Dr. Denkl & Partner, attorneys at law, tax consultants, chartered accountants, Duesseldorf  
  • Head of Legal Department Europe Africa Region (Senior Management) of a multinational company
  • Founder of the Law office Luters-Thümmel with further representations in Riga/Latvia and Brussels/Belgium in cooperation with Kronbergs Čukste Levin and Keuleneer, Vanneste, Van Varenbergh, Verhelst, Derveaux
  • Founding Partner of the Expert Platform 'Compliance Complicen' www.complicen.cc