Morphogenesis – the generation of biological shape and form – is fascinating a fascinating process, and its study promises to shed light on a wide range of developmental defects and inform strategies for tissue engineering and regeneration. Recently, the experimental study of morphogenesis has thrived due to significant increases in the availability of new molecular biology and imaging technologies. However, to take advantage of the avalanche of data resulting from modern developmental biology studies requires new theoretical tools. We need to be able to automatically extract useful quantitative data from experimental outputs; build biologically realistic and predictive theoretical models; and systematically interrogate and validate these models using the extracted quantitative data. In this talk I will describe several theoretical contributions we have recently made in this area, focussing around the fundamental question of tissue size control.