Economies are transitioning from a linear to a circular model to address global issues such as resource extraction, environmental degradation and waste generation. Cross-Sector Collaboration (C-SC) is an effective means to use resources in a way that is mutually beneficial and integrates sustainable practices into the value chain. The zero-waste aspiration of companies can be achieved through Circular Supply Chain Management (CSCM). Existing literature supports research initiatives in CSCM, but how C-SC influences CSCM is still unexplored. Moreover, the barriers to C-SC for CSCM are untouched and the strategies to overcome these barriers are unmapped. This study fills this gap, assesses the barriers to C-SC for CSCM and suggests a strategic roadmap to overcome these barriers. The study was conducted in three different phases employing a multi-method approach of Agglomerative Hierarchical Clustering (AHC), Fuzzy Delphi and Fuzzy Decision-Making Trial and Evaluation Laboratory (F-DEMATEL). The results reveal that governance barriers and contextual barriers are causal and influence the other barriers. There is a need to enhance the capacity and optimum resource utilisation for developing circular supply chains; it is possible to facilitate CSCM practices only through collaborative efforts across sectors. The study also highlights that government policymaking and regulation, collaborative value capture model and Industry 4.0 technologies are the most effective strategies for managing C-SC for CSCM. This study contributes to stakeholder theory and resource-based view theory by explicating collaboration among cross-sector stakeholders and highlighting the significance of resource optimisation through waste management.