The goal is to begin charting a road map for stability and democracy for the entire region in the years ahead.
Among those attending are Ukrainian President Viktor Yushchenko, Georgian President Mikheil Saakashvili, Romanian President Traian Basescu, Moldovan President Vladimir Voronin, and EU foreign policy chief Javier Solana.
The Lithuanian and Polish presidents, whose countries recently joined NATO and the EU, are co-hosting the Vilnius gathering.
U.S. Vice President Dick Cheney is due to deliver the keynote address.
See also: Interview: Lithuanian President On Building 'Common Neighborhood'
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