1 Funding provided by CRIEPI and the Norwegian Ministry of Foreign Affairs The project has been endorsed by the International Human Dimension Programme/ Institutional Dimension of Global Environmental change (IHDP/IDGEC) Four scenarios have been developed with the view of describing how the future of the global climate regime may evolve. The scenarios range from a deepening of the Kyoto framework to new regimes with multiple treaties. The studies presented here intend to provide a platform for policy makers to debate how the future climate regime may be designed. Introduction The Kyoto Protocol under the United Nations Framework Convention on Climate Change (UNFCCC) is an important first step in the development of a truly global climate regime. However, even if it enters into force the regime will look different than what was originally assumed. The USA has opted out and currently shown no signs of returning. For future negotiations, views are sharply divided between, and among, developed and developing countries on the issue of burden sharing. While the Protocol schedules another negotiation round beginning from 2005 to set further targets beyond 2012, there is a possibility that countries may be looking to develop alternatives to the current framework, particularly if the world’s largest emitters i refuse to engage in the Kyoto process. Bringing the world’s biggest emitter of greenhouse gases back on board is essential to ensure the effectiveness of a future global regime, as is working together with the largest developing countries, where large growth in emissions is expected, and where a huge potential for low-cost reductions exists. Facing up to these challenges, while continuing to develop the details of the current regime, means that the negotiations on a future climate agreement run a risk of stalemate and failure. It is essential that we already now make an effort to identify the problems we will face in the coming rounds of negotiations, and explore policy options that can help overcome them. This study looks at a range of scenarios that countries may wish to consider for a post 2012 framework, illustrating the many possible futures under which the global climate regime may evolve. Up to now, little work has focused on developing regime scenarios that could serve as a pragmatic basis for post-Kyoto negotiations that are set to begin in 2005. In developing the scenarios, efforts have been made to maintain the diversity of approaches, and we have posed three key questions which all scenarios must address. They are: • What does the scenario look like? This requires a description of the emerging regime in the scenario, with details on the institutional design. • How can the envisaged policy regime emerge? This requires a description of the premise, driving forces, and events that will eventually lead to the scenario. • How, and to what extent, will the regime prevent climate change? This requests a description of the potential effectiveness of the regime, and naturally includes the prospect for evolution of the regime over time. This project was conducted as a truly global effort, with intensive and cooperative discussions among key researchers from Europe, Japan, China, Canada, and the USA ii . A series of workshops were held to provide feedback to the scenarios and interaction with policy makers and stakeholders in different regions of the world. Workshops in 2003 were held in Oslo (February and September), Tokyo Briefing Paper Scenarios for the Global Climate Regime by Taishi Sugiyama, Kristian Tangen, Axel Michaelowa, Jiahua Pan, and Henrik Hasselknippe