Reducing food insecurity in the developing world continues to be a major public policy challenge, and one that is complicated by lack of information on the location, severity, and causes of food insecurity. Such information is needed to properly target assistance, evaluate whether progress is achieved, and develop appropriate interventions to help those in need. This research report explores a new method of measuring food insecurity using food data collected as part of household expenditure surveys. Such surveys are routinely undertaken by numerous national governments throughout the developing world, but in the past the resulting food data remained largely unexploited for the purposes of measuring food insecurity. Using data from 12 Sub-Saharan African countries, this innovative and scholarly research by Lisa Smith, Harold Alderman, and Dede Aduayom demonstrates the value of such data for generating estimates of both diet quantity indicators, such as the share of populations that are food-energy deficient, and diet quality indicators, such as diet diversity. While the approach does not permit an annual update of the food security situation due to the time-consuming nature of household surveys, the results indicate that household expenditure surveys are a rich source of data for improving food security measurement. The approach facilitates an improved understanding of benchmarking and progress toward the United Nations’ Millennium Development Goal of halving the proportion of people suffering from hunger by 2015, and similarly of the much-preferred World Food Summit Goal of actually cutting the absolute number of undernourished people in half by that time. We hope that updates to these household-based data sources are done, at minimum, on a five-year basis to enrich the understanding of progress in food security, or the lack thereof.