Our group is applying a reverse-engineering approach to the study of network evolution. We focus on the investigation of pattern-forming networks active during development of dipteran insects (flies, midges and mosquitoes). Our main model system—the gap gene network involved in segment determination during early development—will serve as one of the test cases for the reverse-engineering methods during this project. It is an ideal network to study in this context, since it represents a typical developmental gene regulatory network with a moderate number of components, but high spatial and temporal regulatory complexity. Comprehensive, quantitative datasets of spatial gap gene expression patterns are available. Our group has extensive expertise in data acquisition/quantification, global non-linear optimisation, and data/model analysis by means of graphical and numerical methods.