Once established, a 25-nation European Union (EU) would be a formidable market of 500 million people and producer of more than 20% of the world's goods. And the process of adding 10 former communist countries to the EU's current roster of 15 nations is underway. But the process of adapting former command economies to market economies promises to be drawn out and, in some cases, arduous. The Czech Republic, Estonia, Hungary, Poland, and Slovenia are likely to be the first five to gain EU membership. Bulgaria, Latvia, Lithuania, Romania, and the Slovak Republic might have to wait five years--or more.