Detailed numerical simulation has become central to the development and optimisation of low emissions combustor design. The comparative simplicity of the chemical kinetics describing H2 / CO combustion presents particular opportunities for the detailed investigation of the interaction between fuel-specific chemistry and the turbulent combustor flow field. The Cranfield component of the study will provide fundamental data on the underlying combustion properties of the representative reactant mixtures from a combination of laboratory experiment and numerical simulations with detailed chemistry ( embracing flammability limits, burning velocities, extinction strain rates, ignition delay times). These will be incorporated in partially premixed combustion models that seek to account for those additional factors arising in hydrogen-rich flames such as the effects of thermo-diffusive instability. This is a distinguishing feature of lean premixed hydrogen combustion where significant non-unity Lewis numbers effects are encountered. The computational study will be complemented by tests, at representative conditions of temperature and pressure, of a selection of the more promising lean burning premixed or micro-diffusion flame approaches identified in the programme, again with particular emphasis on flame stability. Comparison will be made between model prediction and experiment for purposes of model validation and concept refinement.