The project will gather comparable data on immigration law and policy in 26 countries between 1960 and 2010. The data set will be developed by a Luxembourg-based team of researchers in collaboration with teams of researchers in the USA (Harvard University), the Netherlands (Amsterdam University), the United Kingdom (London School of Economics) and Australia (Sydney University). The project will combine expertise from legal scholars, political scientists, economists, and demographers. We will examine seven major categories of immigration law and policy, covering the economic immigration, family immigration, students’ immigration, acquisition and loss of citizenship, humanitarian protection, preferential bilateral agreements and policies relating to undocumented migration. The Luxembourgish team will be in charge of the coding for four countries: Luxembourg, Germany, France and Switzerland. We intend to code the immigration policies for those four countries for the major turning years between 1960 onwards and for the seven categories of immigration policy. The data collected will be integrated in the international database covering the 26 major destination countries in terms of immigration.This new database will considerably contribute to the existing literature on the determinants of immigration flows; at the same time, it will allow for investigating which dimensions of immigration policies make a difference and for a comparative analysis of the effectiveness of immigration policies in their various dimensions across European countries. It should be of immense value to researchers in a wide variety of academic disciplines. It will be useful to economists interested in explaining immigration flows and their economic effects, to sociologists examining the social and cultural consequences of immigration, to political scientists interested in explaining immigration policies and the political impact of immigration, and to legal scholars studying the rights granted to immigrants and refugees in different countries. All the data will ultimately be made available to scholars in a publicly accessible archive. We also plan to produce a co-authored report, describing the new data in detail, reporting summary statistics and other analysis, and providing a clear guide to using the data.