This report is an introductory assessment of migration flows to and from Poland in the aftermarth of the EU enlargement on 1 May 2004. Following statistics were taken into account: In the part analyzing mobility of Polish nationals: (1) - Border crossing, (2) - Emigration form Poland. In the part analyzing immigration to Poland: (1) - Border crossing, (2) - Applications for refugee status, (3) - Grants for settlement, (4) -Applications for Polish citizenship, (5) - Mixed marriages. The data comes from various sources mainly from the Ministry of Internal Affairs, local governments and SOPEMI reports compiled by the Institute of Social Studies, University of Warsaw and the Polish Central Office for Statistics.