It is with great sadness that we learned of the death on January 20 of our valued author and friend Thomas F. Mayer. An individual of great courage and prodigious learning, Mayer was perhaps the world’s leading authority on the papal institutions of the seventeenth century. He examined the subject in two volumes already published by Penn, The Roman Inquisition: A Papal Bureaucracy and Its Laws in the Age of Galileo (2013) and The Roman Inquisition on the Stage of Italy, ca. 1590-1640 (2014), and in a third, The Roman Inquisition Trying Galileo, that will appear early next year. Altogether a monumental work, and one we wish the author were here to see completed.