There is growing concern that satisfying societal demand for food over coming decades will be increasingly challenging. Much of the debate centres on increasing food production which has always been-and remains-an important strategy to alleviate food insecurity. However, despite the fact that more than enough food is currently produced per capita to adequately feed the global population, about 925 million people remained food insecure in 2010. Meeting future demand will be further complicated by deleterious changes in climate and other environmental factors (collectively termed 'global environmental change', GEC). This paper lays out a case for a food systems approach to research the complex food security/GEC arena and provides a number of examples of how this can help. These include (i) providing a framework for structuring dialogues aimed at enhancing food security and identifying the range of actors and other interested parties who should be involved; (ii) integrating analyses of the full set of food system activities (i. e. producing, storing, processing, packaging, trading and consuming food) with those of the food security outcomes i. e. stability of food access, utilisation and availability, and all their nine elements (rather than only food production); (iii) helping to both assess the impacts of GEC on food systems and identify feedbacks to the earth system from food system activities; (iv) helping to identify intervention points for enhancing food security and analysing synergies and trade-offs between food security, ecosystem services and social welfare outcomes of different adaptation pathways; and (v) highlighting where new research is needed. © 2011 Springer Science + Business Media B.V. & International Society for Plant Pathology.