The enlargement of the European Union has always been an issue of intense public debate, particularly in Germany. It is often argued that enlargement - also referred to as regional integration - causes a rise in unemployment among German workers, a fall in their wages and an increase in wage inequality. It is a fact that Germany did witness rising unemployment and wage inequality during the 1990s. But was this really caused by import substitution? Was it a result of immigration of foreign workers? Or were there other factors at play that contributed to these trends? If so, what are these factors? The author Deniz Ortac provides an introduction to the theory of trade and migration effects on the labour market and then summarises key findings of the empirical literature. Finally, the author offers an alternative approach to model the impact of trade and migration on the German labour market. This book is addressed to trade, migration and regional integration economists, relevant industry bodies and every person with an interest in the current debate.