Balthazar (West Chester Univ.) has conceived this historical dictionary as an academic textbook in alphabetical format, with entries for important composers, librettists, performers, impresarios, publishers, individual keystone operas, major cities, and terms. In entries for composers and other persons, Balthazar keeps biographical information to a minimum and emphasizes commentary on their achievements. Articles dealing with composers (e. g., Mozart, Verdi), librettists (e. g., Da Ponte, Boito), and singers (e. g., Callas, Pavarotti) present succinct accounts of their unique abilities and achievements. However, several composers lack entries, including Johann Strauss II (his compatriot, Lehár, is included), Humperdinck, and Gershwin, who are still represented in today's repertoire. Included is a useful piece titled "Categories of Opera," which provides cross-references to articles on the most important types of opera and operetta. Balthazar also surveys the contributions that women have made to opera. He provides an extensive bibliography of English-language books, dissertations, and articles published during the last 50 years. This dictionary will be a valuable acquisition for academic libraries with modest budgets. Summing Up: Recommended. Lower-division undergraduates through researchers/faculty.