Dietrich is seconded from the Federal Ministry of Finance where he has worked mainly in the areas of European and International Financial Policy including assignments to the embassies in Montevideo and London. He served for six years as a member of the Advisory Committee on Administrative and Budgetary Questions (ACABQ) at the UN New York. He started his career as civil servant with the Ministry of Labour and Social affairs including a secondment to the ILO/IPEC in Geneva and San José.