The Federal Assembly was the federal parliament of Czechoslovakia from January 1, 1969 to the dissolution of Czechoslovakia on December 31, 1992. It was Czechoslovakia's highest legislative institution. The Assembly building was originally a stock exchange, designed by Jaroslav Rossler and completed in 1938. The space proved insufficient, and after a design competition Karel Prager was appointed to add an extension. He added a modern glass, metal and stone structure around and over the top of the original building. The project was both expensive and controversial.

Between 1995 and 2008, The Federal Assembly Building housed the headquarters of Radio Free Europe/Radio Liberty. As of 2015, it houses the Federal Assembly National Museum. Prager's design has since been copied elsewhere, for example in what is now the Bank of Georgia headquarters in Tbilisi.