The Kyoto Protocol has put a framework in place to reduce industrialized countries’ green house gas emissions through the introduction of market-based mechanisms.One of these market-based mechanisms, the Clean Development Mechanism (CDM), gives emission-reduction projects in developing countries certified emission reduction (CER) credits for each ton of CO2 they reduce or absorb. CERs can be bought by industrialized countries to compensate for their emissions. The sale of CERs can be a significant source of revenue for Sub-Saharan African countries. But first, for a project to be considered as a CDM project, it must be approved by the Designated National Authority (DNA).
The CDM Rulebook is an excellent source of information.