This text examines the relationship between DNA damage and repair, cellular senescence, genomic instability, and aging. The authors provide in-depth discussions of various types of DNA damage, the DNA repair network, and cellular responses to genetic damage to assess their impact on the modulation of aging processes and age-related diseases, including cancer development. Chromosomal Instability and Aging describes cloning genes for human chromosomal instability disorders, the causal factors and consequences of chromosomal injury, the telomere hypothesis of aging, and age-dependant mitochondrial genetic instability. It includes more than 2200 references to facilitate further research, making it an informative and timely guide.