The Czech Republic, Estonia, Hungary, Lithuania, Latvia, Malta, Poland, Slovakia, and Slovenia have now joined the Schengen border-free zone. Border posts and checks will be lifted in these countries on Dec. 21 except at airports—these will be lifted as of March 2008. This will make trade between these countries and the rest of the EU smoother. Foreign visitors can travel freely to all Schengen states on a single visa, and this expansion of the Schengen treaty members is expected to boost the tourism sector.