This briefing note explains how public procurement can contribute to the progressive realization of the human right to adequate food, and how it already does so in a number of countries. It describes why public procurement matters for food and nutrition security strategies, and what it can achieve. It identifies which kind of public procurement should be encouraged, based upon country examples, and identifies five key principles that should be integrated into public procurement schemes and modalities, such as the need to target vulnerable groups; support food accessibility and adequate diets; ensure environmental sustainability; and include participation, accountability and empowerment as strong features of public procurement schemes. It reviews frequently cited ‘obstacles’ to the implementation of some of these principles, including budgetary constraints, institutional and legal issues, and demonstrates that there is room to develop ambitious public procurement policies and programmes. It also addresses potential constraints presented by the WTO Government Procurement Agreement. It ends with a number of recommendations to policy-makers.