The Sacristy is a space of great proportions which includes the apartments of the Ante-sacristy and the vestuary with its collection of garments. The Ante-sacristy is a room of rectangular plan, decorated with paintings by the Italian artists Vincenzo Carducci and Eugenio Caxés, also Francisco Ricci and Luca Giordano.
The Sacristy was designed by Francisco Vergara the Greater and Juan Bautista Monegro, in Herrerian style. The barrel vault with half-moon motifs is lavishly decorated with the paintings of the Neapolitan Luca Giordano. The principal theme is the Clothing of Saint Ildephonsus with the Chasuble, a theme which is found repeated throughout the cathedral as much in paintings as in sculpture. The walls display a great variety of beautifully framed paintings, forming a gallery of very valuable artworks by several great masters. The most renowned are the fifteen by El Greco, including his El Expolio (The Disrobing of Christ) on the High Altar (in late 2013 this was on temporary display at the Prado in Madrid, following a period of cleaning and conservation work there), framed by marblework and two Corinthian columns. There are also paintings by the artists Luis de Morales, Pedro de Orrente, Juan Pantoja de la Cruz, Juan de Borgoña, Luis Tristán, Anthony van Dyck, Francisco Goya (Betrayal of Christ), Bassano the Younger and others.