Successful development of the EU is inevitably influenced by the successful development of its European neighbours, so the EU has always sought close political and trade relations with them. For aspiring members, this relationship has also provided aid and support in their preparations for negotiations and eventual EU accession, tailor-made for their particular needs. This has always included assisting them in fully understanding the EU rules and obligations, and in familiarising them with the way the EU functions.

The EU also provides specific technical help and targeted financial aid for aspiring members that are still dealing with the challenges of reinforcing political stability, democratic institutions, functioning market economies, and prosperity for all their citizens. Programmes such as PHARE (set up in 1989 to help the countries of Central and Eastern Europe that were emerging from communism), ISPA and Sapard (designed to support infrastructure, agriculture and rural development in the candidate countries), CARDS (specifically for the countries of the Western Balkans) and a specific programme for Turkey, have delivered more than 100 billion euros of assistance for aspiring countries and new Member States over the last decade.

More recently a new, comprehensive instrument for all pre-accession financial aid was established to respond to the current needs of enlargement. The Instrument for Pre-accession Assistance (IPA) came into effect in 2007, and has been the channel for assistance to Turkey and the Western Balkans. From 2007 to 2012 IPA has allocated about 10 billion Euros to support numerous projects in Southeast Europe. Since Iceland has become a candidate, the European Commission has amended the Instrument in order to include also Iceland as a beneficiary. In conjunction with the financial aid, the EU will continue to collaborate with all these countries to carry out the adjustments that will help prepare them for a smoother integration into the EU.

The current candidate countries are Croatia, Iceland, the former Yugoslav Republic of Macedonia, Montenegro and Turkey. Formal negotiations on EU membership were opened with Croatia and Turkey in October 2005 and with Iceland in July 2010. The former Yugoslav Republic of Macedonia became a candidate in December 2005. Montenegro was granted candidate status in December 2010.The EU has repeatedly confirmed that the rest of the Western Balkans (Albania, Bosnia and Herzegovina, Serbia, as well as Kosovo*) also share the European perspective. They are known as potential candidates.