After the accession of ten new member-states in 2004, the number of official EU languages increased from eleven to twenty. In 2005, the Council of the European Union decided to expand the existing legal framework for Irish and for other languages, such as Basque, Catalan and Galician, which are official in all or part of the territory of a given member-state. On 1 January 2007 Bulgaria and Romania joined the EU, increasing the number of official EU languages still further. This book addresses the challenge of respecting linguistic diversity within the EU and is intended as an introduction to the issue for those not already familiar with EU law. It also provides an analysis of the potential of the Charter of Fundamental Rights of the European Union to enhance respect for linguistic diversity.