Maintained throughout the Roman empire, the Theater of Pompey had fallen into ruins by the early 12th century. By 1762 its remains had been identified, and in 1835 the architect Luigi Canina produced a graphic reconstruction revised by Victoire Baltard in 1837. An 1865 excavation recovered a colossal bronze Hercules and new sections of the theater, but no further studies followed. In 1996–2001 Richard Beacham and James Packer documented the accessible remains, studied the earlier reconstructions, and assembled a catalogue of all references to archaeological finds. Their research led to a small excavation in the ambulacrum that partially cleared modern rubble and recovered ceramic and marble fragments. Foundation trenches for elevators in the southeast court of the palace revealed a deposit of 12th- to 15th-century pottery, part of a vault from a radial corridor in the theater, and a frescoed wall fragment. The new documentation and excavation plans also provide important new information on the Pio Palace and the Temple of Venus Victrix. This article provides a more accurate picture of the architecture, appearance, and situation of the theater and related buildings than previously available and offers considerable promise for subsequent excavations.