Understanding the biological basis of aging has fascinated people throughout recorded history, and is one of the great remaining scientific questions. The question has never been more important than now, as we anticipate the impact that a rapidly growing older population will have on the social, political, and medical landscape over the next 50 years. There is increasing evidence that aging involves damage to the genome, and it is certainly the case that such damage explains much of the coupling of most cancers to aging. This volume brings together expert reviews on issues related to the role of chromosomal instability in the modulation of life span and health.