We study the principles of tissue organisation. By developing and integrating cutting-edge spatial genomics, artificial intelligence and gene editing tools, we build reference maps that eveal how changes in DNA and in the environment reshape the cellular circuits underlying phenotype. Tissues are where cells do their work, and where disease begins and progresses, so the quantitative data we generate offer a route to better treatments. Understanding tissue physiology also lets us design predictive models that recapitulate disease in a dish.