One third of the materials covered in this book were purchased by Henry Clay Folger (1857-1930), the American industrialist and eventual Chairman of the New York Company Standard Oil. The remaining two thirds were collected following his death. Together with his wife Emily Jordan Folger (1858-1936), they assembled one of the most important private libraries in the US. Their invaluable collection of books and manuscripts is housed in the Folger Shakespeare Library, and since the library's opening in April 1932, many further materials have been acquired. This book covers all the known music manuscript materials in the library, occupying 168 dedicated entries. These sources range from fragmentary items to ones of considerable importance, and date from the ninth to the twentieth centuries. The great bulk of the music manuscripts have hitherto escaped examination, and many compositions are not recorded in relevant work lists in New Grove II. The music includes stage works, secular and sacred vocal pieces as well as instrumental compositions. There are autographs by well-known composers and musicians such as Hector Berlioz, Sir Henry Rowley Bishop, Charles Dibdin, John Liptrot Hatton, Felix Mendelssohn, Roger Quilter, Anton Rubinstein, Clara Schumann, Sir Arthur Seymour Sullivan and Niccolo Antonio Zingarelli. Selected sources with music by Henry Purcell have been familiar to scholars for some decades, though the library owns further manuscripts of his music that have previously been overlooked. Other leading British composers represented include Thomas Augustine Arne, William Byrd, George Frideric Handel, William Hayes, King Henry VIII and William Lawes. Continental composers feature among the library's sources, such as Gregor Aichinger, Christian Erbach, Charles-Francois Gounod, Francisco Guerrero, Joseph Haydn, Wolfgang Amadeus Mozart, Clemens non Papa, Gioachino Antonio Rossini, Giuseppe Verdi and Tomas Luis de Victoria, to mention only a handful of figures. A large number of sources and compositions are identified and revealed in the present book for the first time and until recently many of them were uncatalogued. Richard Charteris is Professor in Historical Musicology at the University of Sydney.