The project aims at providing insights for European climate policy, while assessing different greenhouse gas emission reduction strategies for the 2010 and 2030 horizons, by world region. The study combines the use and development of a world energy sector model (POLES) and of a General Equilibrium Model (GEM-E3), with policy oriented research on emission targets and flexibility scenarios, in the perspective of sustainable development. These scenarios will encompass issues of targets, as well as rules for "What" and "Where" flexibility in the compliance to the Kyoto Protocol. They will also address post-2010 targets, in terms of possible entitlements for "Annex B" and "Non-Annex B" countries and the issue of "When" flexibility. For the full economic assessment of the scenarios, the models will be improved in order to model carbon sinks and other than energy CO2 Greenhouse gases and to account for international interdependencies in mitigation strategies.