The Cobimfo project is positioned in the context of the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries program (UN-REDD, http://www.un-redd.org). This collaborative partnership between FAO, UNDP and UNEP was created in response to, and in support of, the UNFCCC decision on REDD at COP 13 and the Bali Action Plan. Currently, deforestation and forest degradation, through agricultural expansion, infrastructure development, destructive logging, fires etc., account for 17% of the global greenhouse gas budget (IPCC, 2007). The REDD program supports countries to develop capacity to reduce emissions from deforestation and forest degradation and to implement a future REDD mechanism in a post-2012 climate regime. Worldwide, especially pristine tropical forests are declining rapidly as the consequence of rapid changes in land use (agricultural expansion, commercial logging, plantation development, mining, urbanization) (Hoare 2007). REDD was initially limited to reduce CO2 emissions from deforestation in developing countries, but was soon expanded to forest degradation. The so called Bali Action Roadmap further broadened REDD to REDD+ to include forest conservation, sustainable management of tropical forests and enhancement of forest carbon stocks. REDD+ will create via the global carbon market a financial value for the carbon stored in forests, offering incentives for developing countries to reduce emissions. It is predicted that financial flows for greenhouse gas emission reductions from REDD+ could reach up to US$30 billion a year. This significant North-South flow of funds could reward a meaningful reduction of carbon emissions and could also support new development.The REDD+ program may provoke ecological damages and/or promote ecological co-benefits. In this respect, biodiversity is of main importance since it plays an essential role in the services that ecosystems can provide to the society in the short and long term. Ecosystem services are the profits obtained by people from ecosystems, and include (1) provisioning services such as food, clean water, timber, fiber, and genetic resources, (2) regulating services such as the regulation of climate, floods, disease, water quality, and pollination, (3) cultural services such as recreational, aesthetic, and spiritual benefits, and (4) supporting services such as soil formation soil fertility, and nutrient cycling. Although tropical forests cover less than 10% of the global land area, they represent the largest terrestrial reservoir of biological diversity, from the gene to the habitat level. Climate change mitigation through the sequestration of carbon and the protection of biodiversity have both been high priorities in the scientific, governmental, and civil society agendas of the last few years, but they have rarely been considered in conjunction (Diaz et al., 2009). Within the UN-REDD+ strategy to conserve and protect tropical rainforest systems the sequestration of carbon as a means to attenuate climate change is of primary importance. Biodiversity is generally described as a potential “co -benefit” of forest carbon sequestration, but components of forest biodiversity may overlap to different degrees, trade off with, or be largely independent from those that intervene in carbon sequestration potential (Díaz et al., 2009). Therefore understanding the relationship between C stock and biodiversity as a function of forest management, including forest protection, degradation and forest regeneration, is of main importance. Increased insight in the latter relation are needed to maximize the UN-REDD+ gains, to better address the risks of UN-REDD+ programs, and to avoid substantial biodiversity loss.