Tourism development in Europe tourism: a tool for sustainable development in transition economies ; Belgrade, Serbia and Montenegro, 20 - 21 June 2005 ; impact of European Union enlargement on tourism development in Europe ; Vilnius, Lithuania, 1 - 2 March 2006 ; [this publication contains the proceedings of two UNWTO conferences on "Tourism: a Tool for Sustainable Development in Transitional Economies", held in Belgrade on 20 - 21 June 2005, and "Impact of European Union Enlargement on Tourism Development in Europe", held in Vilnius on 1 - 2 March 2006] (2007)