Rectangular prostyle building. It served as a meeting-place of the 500-member Boule (Senate), made up of fifty citizens, from each of the ten Athenian tribes, chosen by allotment each year. As a legislative body the Senate prepared the bills that afterwards were voted on in the assembly of all citizens (Ekklesia of the Demos). For a time the New Bouleuterion functioned along with the Old Bouleuterion, which apparently because of a lack of space came to be used only as a repository of state archives. The partial preservation of the New Bouleuterion at ground level makes it difficult to establish the arrangement of the benches on the interior. In the second half of the 4th cent. BC the entrance-way acquired a monumental propylon of the Ionic order, that stood immediately south of the Old Bouleuterion