Housed in a Baroque masterwork by Borromini, this former religious residence named for Saint Philip Neri, founder in 1551 of the Congregation of the Oratorians, now contains Rome's Archivio Storico. Like the Jesuits, the Oratorians—or Filippini, as they were commonly known—were one of the new religious orders established in the mid-16th century as part of the Counter-Reformation. Neri, a man of rare charm and wit, insisted that the members of the order—most of them young noblemen whom he had recruited personally—not only renounce their worldly goods, but also work as common laborers in the building of Neri's great church of Santa Maria in Vallicella. The Oratory itself, once headquarters of the order, was built by Borromini between 1637 and 1662. Its gently curving facade is typical of Borromini's insistence on introducing movement into everything he designed. The inspiration here is that of arms extended in welcome to the poor. The building houses the Vallicelliana Library found by Philip Neri, and the courtyard is usually accessible during the library's opening hours.