This article explains the technical potential of C (carbon) sequestration in world soils for mitigating climate change and describes its positive impacts on agronomic productivity and global food security through the improvement of soil quality. It also supports the idea of economic development through the provision of payments to farmers in developing countries for their stewardship and enhancement of ecosystem services. These would be generated by their use of recommended management practices for improved agriculture. The technical potential of C sequestration in soils of terrestrial ecosystems and restoration of peat soils is _3 Petagram (Pg) C/yr (i.e. 3___1015 g_Euro Surveillance (Bulletin Europeen Sur Les Maladies Transmissibles; European Communicable Disease Bulletin)_3___109 tonnes C/yr) or 50 ppm draw down of atmospheric CO2 by the end of the 21st century by increasing the soil C pool at a rate of 1 Mg/ha/yr. Depending upon climate and other variables, this could increase cereal and food legume production in developing countries by 32 million Mg/yr and roots and tubers by 9 million Mg/yr. It is precisely this strategy which would have received broad political support at the COP-15 meeting in Copenhagen in December 2009 from developing countries, emerging economies and the industrialized world. Addressing the issue of food-insecurity and global warming through sequestration of C in soils and the biota, along with payments to resource-poor farmers for the ecosystem services rendered, would be a timely win-win strategy.