In social life cycle assessment (S-LCA), the use of a participatory approach to define and select assessment criteria and indicators (C&Is) is recommended given the specificity of social issues, but it has been, for now, rarely implemented and presents methodological challenges. Within a participatory action research project gathering academic researchers and field actors, we tested the applicability of configuring a C&Is list for S-LCA, together with chain actors of three alternative food distribution systems active in Belgium. The purpose of this article is to present the results of this work and to examine the methodological limits, requirements, and contributions of such an approach. The participatory approach is an appropriate method to build a list of C&Is standing out from other studies, with the identification of ambitious and innovative C&Is relating to value-chain actors (VCAs) stakeholder category, on chain governance and transaction modalities. In our case, it required an adaptation work of C&Is to the S-LCA requirements and the use of a specific theoretical approach to articulate C&Is within a coherent framework. Finally, this kind of work seems useful to give ground to the S-LCA Guidelines’ list of subcategories, which was built through a rather top-down expert-based approach.