The enlargement of the EU to embrace Central, Eastern and Southern Europe is usually analysed from political and economic points of view, but the current process also has significant legal implications, which this edited collection aims to explore. Written by scholars and officials from both the EU and the new Member States, the contributions cover three main themes. The first chapters examine how Treaty-based accession conditions have been elaborated and controlled to meet the particular needs of the present process. The second part of the book analyses the modalities of accession and in particular the unprecedented "pre-accession strategy" established by the Union with a view to monitoring the transformation of the candidate countries' legal orders. The final group of chapters envisage the impact of enlargement on the EU institutions and policies, both internal and external.