The topic of the third volume of the Croatian Accession to the European Union series is joining the Union and its requirements as a key to the transformation of society. From the experience of other countries, it is known that joining the EU really is a powerful stimulus and actuating force for the implementation of reform programmes. It should not be forgotten, irrespective of the requirements and conditions for EU accession, that Croatia is still in need of reforms to transform society for its own good. Like the first two publications, this one too endeavours to provide the reader a deeper insight into some of the political and economic problems of joining the EU.