Currently there is much interest and excitement in the understanding of how cells undergo the process of apoptosis or programmed cell death. Understanding how, why, and when cells are instructed to die may provide insight into the aging process, autoimmune syndromes, degenerative diseases, and malignant transformation. This review focuses on the development of apoptosis and describes the process of programmed cell death, some of the factors that incite or prevent its occurrence, and finally some of the diseases in which it may play a role. The hope is that in the not too distant future we may be able to modify or thwart the apoptotic process for therapeutic benefit.