We propose to enhance the operations of the Famine Early Warning Systems Network (FEWS NET), the US Agency for International Development (USAID) decision support system for international food aid programs, through the integration of a custom instance of NASA's Land Information System (LIS). We will create a land data assimilation system specifically for the domains, data streams, and monitoring/forecast requirements associated with food security assessment in data-sparse, developing country settings. USGS/FEWS NET presently handles a wide range of gridded satellite remote sensing and atmospheric model data products from NASA and NOAA to monitor and forecast crop growing conditions in the most food-insecure countries of the world. The new FEWS NET Land Data Assimilation System (FLDAS) will be developed in partnership with NASA/GSFC, and implemented to achieve more effective use of limited available hydroclimatic observations. FLDAS will transition into long term, routine use at USGS for FEWS NET decision support. We will test FLDAS specifically as a tool for production of seasonal food security outlook maps. Benchmarking the skill of these maps, before and after FLDAS implementation, will document improved famine early warning. FEWS NET will gain the capacity to make ensemble runs for weekly and seasonal forecasts of land surface variables, and will also be positioned to apply IPCC climate change modeling results to produce 21st century scenarios of land surface states relevant to food security assessments. State-of-the-practice land data assimilation methods will be applied to the decision-making process for U.S. foreign assistance programs that safeguard the lives and livelihoods of tens of millions of the world's poorest and most vulnerable people. The relevance and efficacy of NASA Earth science programs will be highlighted by this integration of results into an internationally well-known and credible U.S. government decision support system.