Vicki Lundblad employs a single-cell genetic system to study the interplay between the activities that lengthen and shorten telomeres. Her group tweaks specific genes in baker’s yeast (the same organism used to make bread and wine), and observes how chromosome ends respond. Using this strategy, her laboratory pioneered the discovery of the protein subunits of telomerase and uncovered mechanisms that control telomere shortening. Lundblad’s group also developed a high-resolution assay that detects very small changes at each telomere as a cell divides. Using this assay, her group has identified a protein complex that inhibits telomere shortening while it promotes telomerase action. Since these telomere-related proteins are present in mammals, her research also holds lessons about human telomere length control.