During the early 1990s the country turned its economy into one of the most solid in Central Europe. There were many improvements in human rights, such as free speech, democracy, etc. In 1991 Poland became a member of the Visegrad Group and joined NATO in 1999 also with the Czech Republic and Hungary. Polish voters then voted to join the European Union in a vote in June 2003. The country joined the EU on May 1, 2004.