The Temple of Athena at Sounion has long been recognized as one of the most unusual buildings in the architectural history of Greece. Its plan, with columns uniquely on the front and only one side, is unparalleled in the Greek world. Excavations of the temple and other buildings there, however, were complicated by the fact that many architectural pieces from the site had been reused in a Roman temple in the Athenian Agora. Here, Barletta provides a fascinating examination of the early excavations at Sounion, the debate over who was worshipped at the so-called Small Temple within the sanctuary, the varied architectural influences on the Temple of Athena, and the later use of its architectural pieces in the Athenian Agora. Building on unpublished work by William B. Dinsmoor Jr. and Homer A. Thompson, this study represents the first comprehensive view of the temple and its sanctuary.