This acclaimed edition is making available authentic versions of the works of a key figure in the history of opera. "Gli equivoci nel sembiante" (1679), Scarlatti's first opera, is a comedy of mistaken identities and amorous intrigues in the pastoral mode. It was one of the most popular and widely performed works of the composer's long career. A small cast and simple scenic requirements make it an ideal work for performances today. In preparing the score presented here, Frank A. D'Accone compared the six extant manuscripts. His introduction sketches the opera's history and discusses performance practice. A translation of the libretto is appended. Donald Jay Grout is Given Foundation Professor of Musicology Emeritus, Cornell University Frank A. D'Accone is Professor of Music, University of California, Los Angeles. Scarlatti operas already published: "Eraclea, Marco Attilio Regolo, Griselda, The Faithful Princess, Massimo Puppieno, and La Caduta de' Decemviri."