The Kyoto Protocol provides for three mechanisms that enable developed countries with quantified emission limitation and reduction commitments to acquire greenhouse gas reduction credits.  These mechanisms are Joint Implementation (JI) for the creation of Emission Reduction Units (ERUs), Clean Development Mechanism (CDM) for the creation of Credit Emission Reductions (CERs) and International Emission Trading (IET). 

Under JI, a project proponent from a developed country with relatively higher costs of domestic greenhouse reduction would set up a project in another developed country which has a relatively low cost.    

Under CDM, a project proponent from a developed country can take up a greenhouse gas reduction project activity in a developing country where the cost of GHG reduction project activities is usually much lower.  The project proponent from the developed country would be given credits for the project, while the developing country would receive the capital and clean technology to implement the project. 

Under the IET mechanism, countries can trade in the international carbon credit market.  This allows countries with surplus credits to sell the same to countries with quantified emission limitation and reduction commitments under the Kyoto Protocol.