For years, Stephen Tsang has been culturing embryonic stem (ES) cells and created the first mouse model for a recessive form of retinitis pigmentosa by applying homologous recombination to ES cell technology. Two elements define his laboratory. First, by leveraging his genetics clinical practice, in which over 1000 retinal patients are cared for, he brings an array of clinical resources to his research, including stem cells and live imaging data. Second, he and his students are recognized authorities in a broad array of state-of-the-art technologies. Most recently, he was invited as a Moderator for the Gene Editing/Rewriting the Genome session during the 65^th American Society of Human Genetics Annual Meeting.