Welcome to the working group for standardization of multicellular model descriptions.
As a community effort, we collect biological benchmark problems and the corresponding representations in alternative modelling formalisms as well as model implementations in specific simulation environments. For this repository see the COMBINE Multicellular Modelling project
The concept for MultiCellML based on SBML Level 3 extensions is summarized here and a prototype to test and run the new language concepts is described here .