The terminals of trigeminal neurons were followed over time in the corneas of living mice by repeated staining with a nontoxic fluorescent dye. The purpose of these observations was to evaluate remodeling of sensory nerve endings in an adult mammal. Video images of topically stained nerve endings within particular corneal regions were recorded initially, and then again after intervals ranging from 4 hr to 30 d. Comparison of the 2 sets of images showed that sensory endings in the corneal epithelium undergo continual rearrangement under normal circumstances. Substantial changes in terminal configuration occurred over periods as brief as a day.