Sustainability has emerged as a central focus in materials science, especially for polymeric coatings like polyurethanes (PU), which play a critical role across diverse sectors, including automotive, aerospace, marine, construction, textiles, wood/furniture, packaging, and electronics. Traditionally prized for their mechanical robustness, chemical resistance, superior film formation, and aesthetic versatility, PU coatings now face growing environmental concerns, regulatory pressures, and consumer demand for eco-friendly solutions. This calls for a paradigm shift toward more sustainable PU coatings that minimize environmental impact throughout their entire lifecycle from raw material sourcing, production, and application to in-service performance and end-of-life management without compromising on quality or durability. Traditional solvent-borne and isocyanate-based systems are under increased scrutiny due to volatile organic compound (VOC) emissions, worker safety risks, and challenges in disposal. In response, recent research highlights a clear transition toward lower-emission, waterborne PU formulations, incorporation of bio-based feedstocks, non-isocyanate synthesis routes, and innovative design-for-recycling concepts such as dynamic covalent networks and vitrimers. Importantly, sustainability in PU coatings is recognized as a multi-criteria optimization problem, requiring a careful balance of performance, scalability, cost-effectiveness, and circularity to meet the evolving demands of industry and society [1, 2].