Partnership for Peace (PfP) is a North Atlantic Treaty Organisation (NATO) project aimed at creating trust between NATO and other states in Europe and the former Soviet Union; 23 nations are members. It was created in 1994, soon after the collapse of the former Eastern bloc. Ten states which were members (Bulgaria, Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Romania, Slovakia and Slovenia) have since joined NATO. On April 26, 1995, Malta became a member of PfP ; it left in October 1996 in order to keep its neutrality intact . During the NATO summit in Riga on November 29, 2006, Bosnia and Herzegovina, Montenegro and Serbia were invited to join PfP after which they joined PfP on 14 December 2006.