First, it studies migration streams since World War II, and reviews major migration policy regimes. Second, it summarizes the empirical evidence measuring wages, unemployment, and occupational choices. Third, it investigates how migrants affects the labour markets of their host countries, and evaluates econometric studies into the wage and employment consequences of immigration. Surprisingly, there is wide evidence that immigration is largely beneficial for receiving countries. There might be phases of adjustment, but there is no convincing evidence that natives' wages are depressed or unemployment increases as a consequence of migrant inflow. However, there is a growing impression that migration does serve less and less the needs of the labour market. This suggests a stronger focus on economic channels of immigration, for which the book provides a conceptual basis and the required empirical facts and institutional background. ÍNDICE 1 K. F. Zimmermann: The Economics of Migration 2 T. Bengtsson, C. Lundh and K. Scott: From Boom to Bust: The Economic Integration of Immigrants in Postwar Sweden 3 P. J. Pedersen: Immigration in a High Unemployment Economy: The Recent Danish Experience 4 A. Barrett: Irish Migration: Characteristics, Causes, and Consequences 5 T. J. Hatton and S. Wheatley Price: Migration, Migrants, and Policy in the United Kingdom 6 J. C. van Ours and J. Veenman: The Netherlands: Old Emigrants -- Young Immigrant Country 7 T. Bauer, B. Dietz, K. F. Zimmermann, and E. Zwintz: German Migration: Development, Assimilation, and Labour Market Effects 8 T. Straubhaar and S. M. Golder: Empirical Findings on the Swiss Migration Experience 9 A. Venturini and D. Del Boca: Italian Migration 10 O. Bover and P. Velilla: Migrations in Spain: Historical Background and Current Trends 11 N. Glytsos and L. T. Katseli: Greek Migration: The Two Faces of Janus 12 T. Bauer and K. F. Zimmermann: An Assessment of Possible Migration Pressure Following EU Enlargement to Central a