Beginning with Debussy, the author traces growing freedom in the use of tonality and the different paths this emancipation took. Central to the book are the achievements of Schoenberg, Bart?k, Stravinsky, and an insistence on the important role of jazz. Webern, Hindemith, and Prokofiev are also seen as important and seminal figures. The ramifications of their achievements and the individual contributions of many other composers born before 1910...