Using the extensive and disaggregated global GINFORS model, consequences of different possible post-Kyoto regimes on the German and European economy and other major economies in the medium run until 2020 are depicted. The approach is very extensive and detailed in comparison to already existing analyses: this holds for the number of explicitly modelled countries (50 and 2 regions) and 41 economic sectors, input-output tables, the bilateral trade flows, the detailed coverage of behavioural parameters, the coverage of energy balances and CO2 emissions as well as for the number and precise economic-political design of simulation runs. Global emissions will double until 2030 compared to 1990 levels without the existence of a far-reaching climate regime after 2012. A unilateral commitment of the EU would only be a "drop in the bucket", which solely strengthens the credibility of the EU in international negotiations. A stabilisation of global emissions in 2020 compared to 2010, which is consistent with the 2 degrees target of the EU can only be achieved, if all developed and at least the large emerging economies participate and if all possible existing market-ready reduction technologies are used. (C) 2009 Elsevier Ltd. All rights reserved.