This book presents research scenarios which are designed to stabilise the influence of a suite of greenhouse gases. This research was conducted using computer-based research tools known as integrated assessment models. Three modelling groups each independently developed a reference scenario, in which all climate policies were assumed to expire in 2012, and then developed four stabilisation scenarios as departures from their respective reference scenarios. The scenarios in this book are not predictions or best-judgement forecasts from the modelling groups; rather they constitute new research intended to advance understanding of the forces that lead to GHG emissions and ways in which to stabilise GHG concentrations and radiative forcing.