The present volume assembles a comprehensive correspondence between Ranieri Calzabigi (1714–1795) and Wenzel Anton von Kaunitz (1711–1794) in the form of a bilingual critical edition. Ranieri Calzabigi, mainly known to history as the librettist and Christoph Willibald Gluck’s associate on the opera ‘reform’, was a multifaced personality of the 18th century Europe. His interests included not only literature and theatre, but also visual arts, politics as well as lottery games. All of these themes appear in his letters addressed to Wenzel Anton von Kaunitz-Rietberg, one of the most influential figures of the 18th century Austria, who served as Staatskanzler to three Emperors and was an important maecenas of arts.