What seemed just barely possible when Léon Poliakov undertook to write a complete history of anti-Semitism in the mid-1970s would strike most serious historians as the height of folly today. The torrent of specialized studies of the subject in the past quarter-century, covering every period, culture, and continent, may have rendered such a project all but impossible. Even before Poliakov completed his fourth volume, Jacob Katz had wisely decided to confine his classic, From Prejudice to Destruction (1980), to Europe, 1700–1933. Yet there is a need for general treatments of the topic, if only to keep it from disappearing into the forest of ever-narrowing monographs and to help non-specialists make sense of a problem that shows no sign of going away.