The Subgroup on Cell and Developmental Biology brings together researchers who are interested in understanding cell and developmental biology phenomena using quantitative approaches. Cell and developmental biology has long proven a fertile ground for mathematical modeling and, with recent advances in microscopy, image analysis, and fluorescent reporter methods, it is becoming an increasingly quantitative discipline. We are now able to constrain mathematical models of developmental processes, for example through parameter estimation, increasing the potential of such models to be used in a predictive way. The objective of this Subgroup is to accelerate these efforts, by supporting and advancing the use of mathematical modeling as part of the ‘toolkit’ of cell and developmental biology.