Lithuania and Poland have deep and intensive bilateral relations. It can be said that the strategic partnership between Lithuania and Poland is no longer a matter that exists only in the rhetoric and documents of politicians. However, changes in the international environment and in Poland’s domestic politics lead to concerns about the sustainability of the state of these relations and raise the question how further they can be strengthened. Lithuania and Poland work closely in bilateral and multilateral formats in the European Union and NATO. However, opportunities to strengthen Lithuania’s and Poland’s relations through regional cooperation still remain untapped: except for the Eastern Partnership, Lithuania and Poland do not work closely in any regional cooperation format.