This project addresses a serious bottleneck to the widespread availability of engineered tissues for clinical use: Currently, building of new tissues requires inefficient, manual manipulation that is time-consuming, labour-intensive and introduces high variability in the finished products. Relieving this limitation has implications for both health and wealth. The project will capitalize on the skills of its network of laboratories to build and demonstrate a technology for controlling the development of engineered tissues by optogenetics and closed-loop, self-correcting control. The core technology combines machine vision and computer modelling with optical feedback, through which the computer can alter the behaviour of precisely those cells that need to be stimulated/inhibited, for the tissue to develop toward the planned template. Optical sensitivity will be conferred on cells by synthetic biological techniques. One set of demonstrations will manipulate the growth and differentiation of these cells directly. A more advanced set will use light-sensitive production of signalling molecules by engineered cells to connect optical control to the control of normal, non-engineered cells as could be used for clinical tissue engineering, in 2- and in 3-dimensional systems. Our proposal includes plans for dissemination and academic, industrial and social impacts.