The food provisioning system of any city across the globe, whether small or large, is always a hybrid food system, i.e., combining different modes and sources of food provisioning and consumption (institutional, retail, street foods). Some cities are mainly, though not exclusively, fed by urban, peri-urban and nearby rural farms and food processors, while other cities rely largely, though not entirely, on food produced and processed in other countries or continents.

Rapid urban growth; growing urban food and nutrition insecurity and unbalanced food availability, distribution and access are challenging traditional thinking on how cities are fed. The year 2015 marked the signing of the first international protocol by cities calling for development of more sustainable and resilient urban food systems. The protocol, the Milan Urban Food Policy Pact, is signed to date (mid 2017) by over 140 cities. Signatory Mayors from cities in the Global North and South pledged to develop actions and strategies to improve their urban food system.

Urban expansion goes hand in hand with an increase in the demand for natural resources (land, water), which provide vital food and ecosystem services to cities, as well as with increased challenges in terms of economic efficiency, land use and land rights. Large scale conversions of agricultural land to non-agricultural uses have caused, and may also cause in the future, problems in cities and rural areas with regards to drainage systems and flood retention, disruption of the drinking water supply, temperature increases, environmental pollution, and increased vulnerability to disruptions in safe and nutritious food availability and supply, especially in areas affected by climate change.

Coherence across policies on sustainable urbanisation, food and nutrition security, environmental and natural resource management, rural development and sustainable agricultural production, distribution, marketing and consumption is needed to address this issue. City Region Food Systems (CRFS) are considered to offer a lens through which this coherence can be addressed at a specific territorial level. They can be a key tool to operationalise the linkages between Sustainable Development Goal (SDG) 2 (food security, nutrition and sustainable agriculture), SDG 11 (inclusive, safe, resilient and sustainable cities), SDG 12 (sustainable production and consumption) along with several of the other SDGs. CRFS need to be embedded within broader legislation, specifically the ‘Right to Food’ and the ‘Right to the City’, acknowledging the need to guarantee both urban as well as rural food and nutrition security, as well as to regulate (unplanned) urban expansion on agricultural land in order to safeguard food and ecosystem services.
This is in line with the recently adopted  New Urban Agenda (October 2016) that emphasises the need for cities to ‘strengthen food system planning’ and recognises that dependence on distant sources of food and other resources can create sustainability challenges and vulnerabilities to supply disruptions. The agenda includes a commitment to: ‘Support urban agriculture and farming, as well as responsible, local, and sustainable consumption and production, and social interactions, through enabling accessible networks of local markets and commerce as an option to contribute to sustainability and food security’.