 Spahn obtained his doctoral degree in Economics from the Free University of Berlin and has worked at various institutions such as Harvard University in Cambridge, Massachusetts, the Australian National University in Canberra, and the Organisation for Economic Co-operation and Development in Paris.After his retirement in 2005, he served as Macro Fiscal Advisor to the Minister of Finance and Treasury of the Council of Ministers of Bosnia and Herzegovina, and became the founding Executive Director of the House of Finance of Goethe University in Frankfurt am Main.He was also a member of the Independent Commission on Funding and Finance for Wales in the United Kingdom.