"Programmed cell death (PCD) plays important roles in animal development, and its original discovery dates back to 1842 when Karl Vogt reported that cell death is associated with removal of the notochord during amphibian metamorphosis. During the past two decades, dramatic progress has been made in understanding the biochemical basis of the most prominent form of naturally occurring PCD, termed apoptosis. This volume illustrates both the remarkable advances that have been made in elucidating pathways and detailed biochemical mechanisms to explain key events during apoptosis, but they also reveal the many unresolved questions and unexpected new opportunities that we still face for understanding the physiological regulation and function of PCD."