The economic and legal implications of the interrelationship between carbon sequestration programs and biodiversity are analyzed. Firstly, the current,treatment of this issue under the Framework Convention on Climate Change process is presented. Secondly, the implications of carbon incentives for existing forests are studied (basing the analysis on an extension of the Hartman model including carbon sequestration and biodiversity values). Then, the expected influence of this policy on decisions about which type of forest to use for afforestation and reforestation is discussed. An. optimal control model is used to analyze the choice between two types of forests: (i) one with high timber and carbon sequestration values but lower, or negative, biodiversity values; and (ii) one with lower timber and carbon sequestration benefits, but with high biodiversity values. Finally, the relationship between the Kyoto process and the Convention on Biological Diversity is investigated, to assess whether or not the latter is expected to have any influence on the outcomes obtained in the analysis above. Results show that creating economic incentives for carbon sequestration may have negative impacts on biodiversity, especially for afforestation and reforestation programs. (C) 2003 Elsevier B.V. All rights reserved.