Aviation and shipping are growth sectors estimated to produce a high proportion of carbon dioxide emissions in industrialised countries during the next decades but are currently not accounted for in national inventories of greenhouse gases. If these emissions are not accounted for, any policies to achieve a concerted greenhouse gas emissions reduction target will be infective because of faulty and incomplete accounting. We are developing a model that enables policy makers to explore implications of an energy system as a whole, or by its components, and to compare it with competing options. We are also refining the energy-carbon scenarios for the UK produced in Tyndall's Phase 1, creating new scenarios for other countries, and producing detailed carbon footprints for energy and transport.