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The world population has increased from 2–10 million at the dawn of settled agriculture about 10–12 millennium ago to 6.5 billion in 2006, and may stabilize at 10–12 billion by 2100. Most of the future increase in world population will occur in developing countries where the natural resources are already under great stress, and where most of world's food?insecure population lives. Rapid increase in population, especially between 1700 and 2000, caused large scale conversion of natural ecosystems to agricultural land uses. The land?use change involved conversion of 1135 million hectares (Mha) of forest and woodland, and 669 Mha of savanna, grassland, and steppe. Similarly, the area under grazing land increased from 530 Mha to 3300 Mha. Agricultural expansion and its intensification, by plowing and irrigation along with use of chemicals: (1) exacerbated the problems of soil degradation that reportedly affects 1966 Mha worldwide of which the large fraction is caused by water and wind erosion, (2) increased irrigated land area to about 280 Mha or 19% of the total cropland area consuming 18,200 km3 for evapotranspiration or 26% of the total terrestrial evapotranspiration, (3) disrupted global biogeochemical cycling of carbon leading to increase in atmospheric abundance of CO2 by 37.5% from 280 ppm in ?1750 to 385 ppm in 2006, (4) accentuated the use of fertilizers and pesticides to increase food production, and (5) caused mass extinction of plant and animal species. Drastic increase in crop yields during the second half of the twentieth century led to increase in per capita global food production despite the increase in world population. However, the global cereal demand (rice, wheat, maize) will increase at the rate of 1.3% per year between 2000 and 2025 necessitating increase in the mean grain yield of these cereals especially in the developing countries. The required cereal grain yield in developing countries will have to be increased from 2.6 Mg ha?1 in 2000 to 3.60 Mg ha?1 by 2025 and 4.30 Mg ha?1 by 2050 even if the food habit of population in emerging economies (e.g., China, India) remains the same. Therefore, a judicious and scientific management of soil and water resources is essential. Degraded soils and ecosystems must be ameliorated, and the depleted organic carbon pool restored so that soils can respond to the use of yield?enhancing input (e.g., fertilizers, improved varieties). Restoring soil quality through improvements in soil organic carbon pool is essential to increasing agronomic yields especially in sub?Saharan Africa (SSA), South Asia, and elsewhere in the tropics with harsh climate, fragile soils, and resource?poor farmers. This strategy requires the adoption of a holistic approach based on sound scientific principles of managing the soil and water resources in accord with social, economic, and political realities of the region.