The church of <i>Il Gesù</i> in Rome, designed by Giacomo Vignola and completed by Giacomo della Porta, must have been by far the most impressive when it was consecrated in 1584. One of the earliest descriptions of the building appeared in 1588, printed and illustrated with woodcuts by the engraver Girolamo Franzini in a guidebook titled <i>Le case meravigliose dell'alma città di Roma</i>. Its essential structural and decorative features which still capture attention are expertly described. The text has become rare because the guidebook no longer included it after the end of the century. It is partly reproduced in a footnote. A bibliography indicates where to find a detailed history of the church. -- AATA