Klezmer is Yiddish music, the music of the Jews of Europe and America, a music of laughter and tears, of weddings and festivals, of dancing and prayer. Born in the Middle Ages, it came of age in the shtetl (the Eastern European Jewish country town), where "a wedding without klezmer is worse than a funeral without tears." Most of the European klezmorim (klezmer players) were murdered in the Holocaust; in the last 25 years, however, klezmer has been reborn, with dozens of groups, often mixing klezmer with jazz or rock, gaining large followings throughout the world.

The Book of Klezmer traces the music''s entire history, making use of extensive documentary material; interviews with forgotten klezmorim as well as luminaries such as Theodore Bikel, Leonard Nimoy, Joel Grey, Andy Statman, and John Zorn; and dozens of illuminating, stirring, and previously unpublished photographs.