We formulate a dynamic core-periphery model with frictions in the job matching process to study the interplay between trade costs, migration and regional unemployment in the short-and long-run. We Þnd that the spatial distribution of unemployment mirrors (inversely) the distribution of economic activities. Further, we highlight a contrast between the short-run and the long-run effects of trade-induced migration on regional unemployment. In particular, an inßow of immigrants from the periphery into the core reduces the unemployment gap in the short-run, but exacerbates unemployment disparities in the long-run.
JEL classiÞcation: F12, F15, F16.Keywords: Integration, Agglomeration, Search frictions, Labor mobility, Regional disparities. * We thank Daron Acemoglu, Giovanni Bruno, Francesco Daveri, Henrik Horn, Gianmarco Ottaviano, Torsten Persson, Diego Puga, Jaume Ventura, Fabrizio Zilibotti and seminar participants at IIES, Stockholm University, University of Cagliari and MIT. We are especially indebted to Robert Shimer and two anonymous referees for very generous and helpful comments. We thank Annika Andreasson for editorial assistance. The usual caveat applies.