From an economic point of view there are good reasons for the free movement of workers not only within a country, but also beyond its borders. Migration is positive for the economies involved in cases where it is triggered by wage and production differences, but distorts these economies if additionally stimulated by net government transfers made via social welfare benefits, taxes and free use of infrastructure.
Demographic, economic and political developments in countries outside of Europe are currently leading to higher immigration flows from these neighbouring regions to Europe, and especially to Germany. This could encourage potential target countries to compete to deter immigrants and could erode their welfare states.
Can Germany Still be Saved? - Theses on the Future of the Republic, Information page
Refereed scientific monographs
Can Germany be Saved? The Malaise of the World’s First Welfare State, MIT Press: Cambridge, Mass., 2007, 356 pages. (Revised and updated translation of Ist Deutschland noch zu retten?); Chapter 8: “EU Enlargementm, Migration, and the New EU Constitution”. To Amazon.
The New Systems Competition, Yrjö Jahnsson Lectures, Basil Blackwell: Oxford 2003, 228 pages. One hardback, one paperback edition; Chapter 3: “The Erosion of the Welfare State”. To Amazon.
Smaller, non-refereed scientific monographs
EU Enlargement and Labour Mobility: Consequences for Labour Markets and Redistribution by the State in Germany, (together with G. Flaig et al.), CESifo Research Reports, No. 2, Munich 2003, 163 pages; (Download, 670 KB).
Co-authored Committee Reports
Report on the European Economy, European Economic Advisory Group at CESifo (with co-authors), CESifo: Munich, fifteen volumes, 2001–2016, introduction and co-authorship respectively. Particularly Bertola, Giuseppe, John Driffill, Harold James, Hans-Werner Sinn, Jan-Egbert Sturm and Ákos Valentinyi, "Chapter 4: Migration in the European Union: Too much of a good thing?", EEAG Report on the European Economy 2015, 2015, 78-96; (Download, 2 MB).
Articles in refereed journals
"Migration and Social Replacement Incomes. How to Protect Low-income Workers in the Industrialized Countries Against the Forces of Globalization and Market Integration", International Tax and Public Finance 12, 2005, pp. 375-393; (Download, 252 KB); CESifo Working Paper No. 1265, August 2004; NBER Working Paper No. 10798, September 2004.
"EU Enlargement, Migration and the New Constitution", CESifo Economic Studies 50, 2004, pp. 685-707.
"Social Union, Convergence and Migration" (together with W. Ochel), Journal of Common Market Studies 41, 2003, pp. 869-896; (Download, 701 KB); CESifo Working Paper No. 961, June 2003.
"The New Systems Competition", Perspektiven der Wirtschaftspolitik 5, 2004, pp. 23-38; (Download, 130 KB). German version: "Der neue Systemwettbewerb", Perspektiven der Wirtschaftspolitik 3, 2002, pp. 391- 407; (Download, 154 KB); CESifo Working Paper No. 623, December 2001; NBER Working Paper No. 8747, January 2002.
"EU Enlargement and the Future of the Welfare State", Stevenson Citizenship Lectures, Scottish Journal of Political Economy 49, 2002, pp. 104-115; (Download, 130 KB); CESifo Working Paper No. 307, June 2000; Working Paper No. 2001_5, Department of Economics, University of Glasgow.
"EU Enlargement, Migration, and Lessons from German Unification“, German Economic Review 1, 2000, pp. 299-314; (Download, 1.1 MB); CESifo Working Paper No. 182, 1999.
"Tax Harmonization and Tax Competition in Europe", European Economic Review 34, 1990, Papers & Proceedings, pp. 489-504; (Download, 969 KB); NBER Working Paper No. 3248, January 1991; (Download, 191 KB).
Academic papers in conference volumes
"The Case for European Tax Harmonization", in: G. Winckler, ed., Tax Harmonization and Financial Liberalization in Europe. Proceedings of Conferences held by the Confederation of European Economic Associations in 1989, Basingstoke 1992, pp. 3-7 (Download, 0.6 MB).
Policy Contributions in Journals and Academic Volumes
"Immigration Following EU Eastern Enlargement", (with Martin Werding), CESifo Forum 2 (2), 2001, pp. 40-47; (Download, 925 KB).
Short Policy Contributions and Newspaper Articles
“Immigration into the Welfare State”, (ref. Project Syndicate Januar 2016).
"The Limits of the German Promised Land", (ref. Project Syndicate September 2015).
"May Day Madness“ (ref. Project Syndicate April 2006), The Japan Times (Japan), Les Echos (Mali), The Namibian (Namibia), Jakarta Post (Indonesia), The Korea Herald (South Korea), Oriental Daily (Malaysia), Daily Times (Pakistan), Business World (Philippines), Lianhe Zaobao (Singapore), Taipei Times (Taiwan), Kapital (Kazakhstan), Die Presse (Austria), L´Echo (Belgium), Ekonom (Czech Republic), Aripaev (Estonia), Vilaggazdasag (Hungary), Logos Press (Moldavia), Danas (Serbia), Sme (Slowakei), Expansion (Spain), Al Ghad (Jordan), Al Raya (Qatar), Al Eqtisadiah (Saudi Arabia).
"There is no European Right to a Place in the Sun“, Financial Times, No. 35/ 067, February 13th, 2003, p. 11; also published in german as "Zwanzig Mezzogiornos“ (Twenty Mezzogiornos), Financial Times Deutschland, No. 31/07, February 13th, 2003, p. 30.
Ifo Viewpoint No. 145: New Migration, May 3, 2013.
Ifo Viewpoint No. 123: The Migration Storm, Jun 7, 2011.
Ifo Viewpoint No. 97: Barbarians or Geniuses at the Gate?, Jul 15, 2008.
Ifo Viewpoint No. 76: Germany: A Land of Immigration?, Jul 31, 2006.
Ifo Viewpoint No. 60: Seven Truths Regarding Immigration, Dec 1, 2004.
Ifo Viewpoint No. 54: Germany, the Welfare Magnet, Jul 20, 2004.
Ifo Viewpoint No. 53: Directive on Free Movement: Free Ticket to the Welfare State, Jul 8, 2004.
Ifo Viewpoint No. 43: Twenty Mezzogiornos, Feb 13, 2003.
Ifo Viewpoint No. 41: Another Unification and More Illusions, Jan 8, 2003.
Ifo Viewpoint No. 25: In Defence of the Free Movement of Labour, May 2, 2001.
Ifo Viewpoint No. 9: EU Enlargement: the Migration Problem, Dec 23, 1999.