Holiness is a challenge for contemporary Jewish thought. The concept of holiness is crucial to religious discourse in general and to Jewish discourse in particular. "Holiness" seems to express an important feature of religious thought and of religious ways of life. Yet the concept is ill defined. This collection explores what concepts of holiness were operative in different periods of Jewish history and bodies of Jewish literature and offers preliminary reflections on their theological and philosophical import today. The contributors illumine some of the major episodes concerning holiness in the development of the Jewish tradition. They are challenged to think about the problems and potential implicit in Judaic concepts of holiness, to make them explicit, and to try to retrieve the concepts for contemporary theological and philosophical reflection. Not all of the contributors push into philosophical and theological territory, but they all provide resources for the reader to do so. Holiness is elusive but it need not be opaque. This volume makes Jewish concepts of holiness lucid, accessible, and intellectually engaging.