The dominant agri-food system’s well-documented failures—biodiversity loss, deepening rural inequalities, and the erosion of small-scale farming livelihoods—have elevated SSE initiatives and social innovation in the agri-food sector and bioeconomy from a niche policy concern to a structural priority. This paper examines how SSE arrangements drive meaningful transformation in agri-food chains while advancing sustainable development at local and regional scales. Through a narrative review of interdisciplinary peer-reviewed literature and key institutional sources, the paper synthesizes evidence that SSE initiatives generate transformation through three interconnected mechanisms: (a) the reconfiguration of governance structures; (b) the deepening of producer–consumer relationships through spatial proximity and relational transparency; and (c) the more equitable redistribution of value across agri-food territories. These findings suggest that place-based SSE models occupy a central—rather than peripheral—role in sustainability transitions and local development. The paper presents a structured analytical framework linking SSE practices to agri-food chain transformation and develops nine concrete policy implications for scaling and sustaining SSE innovations through coordinated collaboration among public, private, and social economy stakeholders. The findings contribute to a sharper understanding of the conditions under which SSE-driven models can foster sustainable, socially inclusive, and community-oriented agri-food systems and of why the solidarity dimension, rather than organisational form alone, is the decisive criterion for identifying genuinely transformative initiatives.
Κώστας et al. (Mon,) studied this question.