Although it is a matter for States to decide,
subject to the fundamental rules of international law, which persons
are their nationals, it is important for States to co-operate and
co-ordinate their nationality laws in order to deal with such issues
as statelessness, state succession and multiple nationality and
their consequences.
That is the objective of the main European legal
instrument in the area of nationality - the European Convention on
Nationality (CETS No.166), which was adopted by the Council of
Europe in 1997 and entered into force on 1 March 2000. Another
important Council of Europe legal instrument in the area of
nationality – the Convention on the Avoidance of Statelessness in
relation to State Succession (CETS No. 200) – was opened for
signature on 19 May 2006.