Plastic pollution has emerged as one of the most urgent environmental and public-health challenges of the twenty-first century, with heightened production, widespread leakage, and rising evidence of ecological and physiological harm. While technological innovations and regulatory interventions continue to evolve, their effectiveness remains limited without corresponding shifts in public awareness and behaviour. This chapter examines why societal understanding, risk perception, and behavioural change constitute indispensable pillars of plastic-mitigation strategies. Drawing on interdisciplinary evidence from environmental science, behavioural economics, and social psychology, the chapter outlines how public misconceptions such as overreliance on recycling, misplaced faith in “biodegradable” plastics, and the belief that individual actions have negligible impact undermine mitigation efforts. It demonstrates that awareness shapes attitudes, consumption patterns, waste practices, and support for policy measures. Empirical studies from India and globally show consistent links between knowledge, willingness to adopt sustainable behaviours, and compliance with regulatory frameworks. The chapter argues that public awareness is not a peripheral component but a central determinant of success in mitigating plastic risks. Informed citizens enable effective policy implementation, support circular systems, and drive the cultural transformation necessary for long-term sustainability.