This definitive study of the life and works of Joseph Haydn represents half a century of research. As a curator of the Gesellschaft der Musikfreunde in Vienna, Dr. Geiringer was in charge of one of the world's leading Hayden collections. His scholarly investigations took him to various monasteries, to libraries in Eisenstadt, Prague, Berlin, Paris, London, and Washington, D.C., and, as a guest of the Hungarian government, to the previously almost inaccessible archives of the Princes of Esterhazy in Budapest. In the past decade, Haydn studies have progressed enormously. A thematic catalog is now available, and a substantial part of Haydn's vast creative output is accessible in critically revised editions. The new edition of has been substantially rewritten to incorporate the results of recent research and to remove the tarnish that had assimilated on the picture of Haydn in the earlier years.