The Co-Design-Driven Sustainability System (CDSS): bridging product design and systemic change in sustainability transitions — insights from two rural Chinese cases

This paper argues for an integrative and transformative approach that connects localised product innovation, Product – Service System (PSS) integration, and macro-level systemic change through the situated and collaborative lens of co-design. Drawing on two long-term participatory action research (PAR) projects conducted between 2018 and 2023 in rural China, we examine how co-design practices evolved across multiple scales of intervention. Through retrospective cross-case synthesis, we identified a recurring trajectory: beginning with product-focused design, progressing through PSS development, and culminating in systemic engagement at institutional and governance levels. Based on this pattern, we propose the Co-Design-Driven Sustainability System (CDSS) framework, which conceptualises co-design as a dynamic, context-responsive process that bridges micro-level practices with broader sustainability transitions. As a practice-informed framework, it enhances understanding of how co-design can align diverse stakeholders, navigate value tensions, and catalyse systemic transformation by linking situated interventions to long-term transition goals. This study contributes to design and sustainability transition research by offering empirical insights from long-term PAR cases, a theoretical framework that integrates multi-scalar co-design into transition pathways, and a methodological approach combining action-based research with retrospective theory building. Future research should explore the CDSS framework’s applicability across diverse cultural and institutional contexts and assess its long-term systemic impacts.