Comparative analysis of international environmental policies and supply chain sustainability.

Sustainability has become a critical strategic priority for organizations, driven by heightened environmental awareness and regulatory pressures. This study examines how international environmental regulations influence firms' environmental policies and supply chain sustainability practices, with a focus on the mediating role of supply chain collaboration and the moderating effects of cultural and institutional contexts. This research aims to explore the pathways through which environmental regulations shape firm-level strategies, assess how collaboration amplifies sustainability outcomes, and analyse cross-country variations in these dynamics. The data were collected from 300 textile firms across India, China, Bangladesh, Sri Lanka, and Pakistan, using structured surveys and interviews with supply chain managers and environmental officers. This study employs Partial Least Squares Structural Equation Modelling to analyse the relationship between environmental regulations, supply chain collaboration, and sustainability outcomes, while also conducting multi-group analysis to compare results across different national contexts. Our findings reveal that stringent environmental regulations significantly enhance supply chain collaboration, which in turn drives improvements in sustainability performance, particularly in environmental dimensions. Our study also identifies a partial mediation effect, indicating that collaboration plays a crucial role in translating regulatory pressures into tangible sustainability gains. However, the impact of regulations on social and economic sustainability dimensions is less pronounced, suggesting that environmental mandates primarily drive ecological improvements. The novelty of this study lies in its integrative theoretical framework, combining institutional, resource dependence, and stakeholder theories to explain how external pressures and internal strategies converge to shape sustainability outcomes. Policy implications suggest that regulators could pair enforcement mechanisms with incentives for collaborative networks to enhance sustainability across diverse national settings.