The United Nations Framework Convention on Climate Change and the Kyoto Protocol were the first agreements in a long and complex regime on climate change. While the UNFCCC set out the framework, the Kyoto Protocol set out targets that were legally binding on Parties in order to reduce greenhouse gas emissions caused by anthropogenic interference. It envisaged among other things a market based mechanism to help countries meet their targets. Developed countries under the Protocol, with a historical responsibility would be the first to cut emissions and their response would enable developing countries to do the same. Developing countries as it were, had no binding targets. Countries with binding emissions targets could use these market-based instruments to meet their obligations. This paper studies the UNFCCC and the Kyoto Protocol in detail. The effectiveness of these market based mechanisms in reducing GHG emissions is a matter of much debate. This paper attempts to study the market mechanisms and their effectiveness in mitigation of GHG emissions. The findings of the study and suggestions are given in the conclusion of the study.