The recognition over the past decade that apoptosis represents a critical element in cell number control in physiological and pathological situations has been well-reviewed (1 –4 ). In addition there is increasing recognition that many of the effects of chemo- and radiotherapeutic agents are mediated by apoptosis (5 –7 ). The seminal work of Kerr, Wyllie, and Currie (8 ), building upon the earlier observations of Glucksmann (9 ) and Saunders (10 ), should be read by those interested in assaying apoptosis because of the excellent photomicrographs that document the morphological features of the process. This is important, because despite considerable progress in the understanding of the mechanistic basis of apoptosis, morphological analysis remains unquestionably the “gold standard” for its assessment and quantitation.