The 1st of May 2004 is being marked by numerous important political events, speeches and festivities. This is appropriate in the sense that on that day ten new member states join the EU. However, “all” that happens on May 1st is that the EU’s acquis communautaire becomes the law in the new member states. In order to make this happen, a decade of intense preparations on both sides was necessary and it will certainly take another decade before the full consequences of this enlargement will be felt. Enlargement should thus be viewed as a process, and not a single event taking place on one day. For a think tank with the motto ‘Thinking ahead for Europe’, enlargement is old news. CEPS researchers have been analysing the many issues surrounding enlargement for at least the last dozen years, when it seemed only a distant dream. Over time the debate has shifted from the basic question of whether countries that had been forced to live under communism for so long would actually be able to qualify for EU membership to the basic policy issues: What will it cost? How will it affect our security? These are the basic issues surrounding any large political project. The following pages provide a brief overview of the main findings of CEPS research on enlargement over the years. We start with an evaluation of the importance of enlargement in quantitative terms (GDP, population, etc.) and then turn to an evaluation of its broad economic impact, which is likely to be small for the old members, but large for the new members. This leads us to issue of the cost of enlargement (for the old EU-15), which is also rather small. The answer to the question ‘what is in it for us’, which is often posed in the old member countries, is thus perhaps disappointing: very little either way, in purely economic terms, there are small costs and small benefits, with probably as small net effect. Here the time dimension becomes important as the benefits will increase over time, faster than the potential costs through the EU budget. We then turn to another issue that has received a lot of attention lately concerning the free movement of labour, drawing attention to the fact that large-scale migration is unlikely at any rate. Finally, we assess the widespread concern that an enlarged EU (of 25 or 27 members) will cause gridlock in the policy-making processes of the EU institutions
