The 2006 Riga summit was held in Riga , Latvia , and highlighted the issue of energy security . It was the first NATO summit to be held in a country that had been part of the Soviet Union . At the April 2008 summit in Bucharest , Romania , NATO agreed to the accession of Croatia and Albania and both countries joined NATO in April 2009 . Ukraine and Georgia were also told that they could eventually become members . The issue of Georgian and Ukrainian membership in NATO prompted harsh criticism from Russia , as did NATO plans for a missile defence system . Studies for this system began in 2002 , with negotiations centered on anti-ballistic missiles being stationed in Poland and the Czech Republic . Though NATO leaders gave assurances that the system was not targeting Russia , both presidents Vladimir Putin and Dmitry Medvedev criticized it as a threat
April 2008 summit
2008 Bucharest summit
History of NATO