Human aging is associated with loss of tissue homeostasis and a greatly elevated risk of debilitating disease, with associated costs in terms of diminished quality of life for the individual and financial burdens on health-care providers. Any advances that hold out the realistic prospect of tackling age-related morbidity are therefore to be welcomed. The recent report by Jeskelioff et al. published in 2010 that telomerase reactivation in adult male mice can not only halt but actually reverse significant tissue pathologies provides a long-awaited proof of principle that it is possible to rejuvenate aged tissues. This review assesses the impact of this new work and considers possible problems and potential benefits of telomerase activation as a therapy to tackle the morbidities associated with human aging.