This detailed survey reassesses the great Romanesque Cathedral and pilgrim destination, Santiago de Compostela, concentrating in the main in establishing an accurate chronology of the building work, and thus attributing the various architectural features to the men we know to have worked on it. The focus is on the west end, which the author argues was left unfinished at the death of Archbishop Gelmirez, but she detects far more of his influence in its design than is often admitted, and she attempts to untangle the work of Gelmirez from his successor in directing the building works, Master Mateo.