In this paper, we use the multi-region version of a detailed bottom-up model MARKAL, to explore avenues for reducing the cost of GHG abatement in North America through energy and emission trading. The setting of the study is the recent Kyoto Protocol, of which Canada and the US are signatories. We consider two alternate levels of Joint Mitigation, the first within North America, the second broadened to include a non-Annex I-country, India. Results indicate overall savings of up to CDN $53 billion (NPV over a 40 year horizon) with North American cooperation, and of about CDN $385 billion when India is included. Inter-regional exchanges and energy policy implications in each region are discussed in some detail.