In Asian-Pacific developing countries, the prevalence of food insecurity has diminished dramatically in the past generation. Despite this, many millions continue to suffer from persistent or periodic food insecurity. The causes of food insecurity are both structural and market-related, including influences of public policy on market operations. The most vulnerable populations are those that simultaneously experience both these forms of insecurity. The places they inhabit tend to have poor-quality land, are exposed to climatic and other environmental risks, or both. These same populations either have relatively weak links with the non-food economy, in which higher wages and better income-earning opportunities make food self-sufficiency less important, or are prevented from accessing opportunities in the non-food economy because of poor or misguided policies.