This article examines whether Eastern enlargement has led the EU 15 member states to enter strategic interactions implying a race to the bottom. The question is whether concerns about welfare migration have led to downward pressure on the EU 15 member states in the form of more restrictive access to their labour markets and adjustments of their social policy benefits. We find little empirical evidence to support the asumption that welfare states with generous benefits and accessible labour markets will become magnets for welfare migration. Nevertheless, the study demonstrates that the EU 15 member states do enter strategic interactions as if such migration would occur. The majority of them have temporarily restricted the free movement of workers from the acceding countries. EU 15 member states with the least restrictions are the ones most active in adjusting their social policies. Strategic interactions in social policy may thus intensify in the future as transitional periods come to an end and future enlargements come into place.