Follow-up activities to the 1996 World Food Summit include the development of a U.S. action plan on food security that contains domestic and international components. This paper presents background information on selected issues relevant for domestic food security planning, especially with regard to food insecurity information systems. It begins with a brief treatment of the conceptual distinctions between food insecurity, hunger, and undernutrition. The paper then describes various types of food consumption, nutrition and health data collected in the national nutrition monitoring system. The problem of selecting baseline indicators of food insecurity and undernutrition for long-range planning is addressed in four sections: (1) a review of the FAO hunger map methodology and the U.S. technical response; (2) a review of selected objectives in the Healthy People 2000 Initiative and in the U.S. response to the International Conference on Nutrition; (3) suggestions of indicators to use from the national nutrition monitoring system in developing baseline estimates of food insecurity and undernutrition; and (4) some broad issues to consider in the selection of these indicators.