ZIG LAYTON-HENRY is Professor of Politics at the University of Warwick and former Director of the ESRC Centre of Research in Ethnic Relations. He is author of The Politics of Immigration (Macmillan, 1992) and editor of The Political Rights of Migrant Workers in Western Europe (Sage, 1990). His main research interests include citizenship, immigration policy and transnational communities. - CZARINA WILPERT is a native of Los Angeles, California and a social scientist at the Berlin University of Technology. Her research addresses multiple aspects of international migration, especially questions relating to the future of the descendants of migrants and the social organisation of migrants from Turkey in Germany. Her most recent work addresses issues of immigrants in the informal labour market and the meanings attached to citizenship and nationality. Dr Wilpert is a core member of the TSER Research Network of the European Community on Working on the Fringes: Immigrant Business, Economic Integration and Informal Practices.