The molecular mechanisms of aging are most fully understood for the budding yeast Saccharomyces cerevisiae. Recent advances in our understanding of aging in this organism have enabled researchers to answer some fundamental questions about the aging process. Is aging due to a multitude of 'mechanisms' or can there be a key few? Can we design single-gene mutations that will prolong life? Can we prolong life whilst maintaining health and fecundity? The various contributing factors to yeast longevity, uncovered thus far, fall into three classes: DNA metabolism, heterochromatin, and metabolic activity. However, these separate classes may actually represent different aspects of the same aging mechanism based on genome stability. This review examines the recent advances in our understanding of yeast aging and discusses their relevance, if any, to the human condition.