There is growing evidence that the current globalised agri-food system is neither sustainable nor resilient. It is responsible for around one third of the global GHG emissions and is a major driver of biodiversity loss. Furthermore, its structure and distribution mode do not provide food security for all and foster socio-economic inequalities between different parts of the planet. Consequently, an increasing number of scientists and members of the civil society are demanding a radical transformation of agri-food systems. The creation of alternative food networks (AFNs) represent a possible first step towards agri-food system transformation. AFNs can incorporate local, indigenous and innovative knowledge and bring together a diversity of actors to connect food production and consumption and create new practices and relationships around food. The creation of AFNs, and ultimately of Alternative Food Systems (AFS), should involve different actors, from farmers to social movements, from policymakers to scientists. AFNs have the potential to contribute to a transformation towards sustainable, just, resilient and productive food systems, but even though they have increased in numbers and organisational forms in recent years, they still remain in a niche. Consequently, scientific evidence of their performance is still limited. This research topic will contribute to a comprehensive, multi-scalar and critical (e.g. including potential counter-effects) understanding of the current state and future potential of AFNs. It will address multiple aspects, ranging from social, economic and environmental aspects to productivity, participation and justice. Moreover, it will highlight the role of governance, power relations and institutions, as well as barriers and ways forward to promote AFNs and their role in food system transformation.