This chapter examines the corporate plastic reduction strategies of companies listed in the BIST Sustainability 25 Index from a marketing perspective. Plastic pollution has become a critical global environmental challenge, requiring firms to move beyond operational waste management toward strategic and institutionalized sustainability approaches. Using qualitative content analysis, the research analyzes the 2023–2024 sustainability reports, integrated annual reports, and Turkish Sustainability Reporting Standards–compliant reports of 25 large-scale companies operating across diverse sectors, including finance, energy, retail, food and beverage, aviation, automotive, and manufacturing. The findings reveal that corporate plastic policies are structured around three main strategic axes: plastic reduction, circularity and recycling, and governance and transparency. Consumer-facing sectors such as retail, FMCG, and aviation emphasize the elimination of single-use plastics, refill systems, and alternative packaging to directly influence consumer behavior and strengthen green brand positioning. In contrast, industrial and energy-intensive sectors prioritize regulatory compliance, recycled raw material use, and supply chain optimization, framing plastics management as a tool for ESG performance and risk management. The study also highlights the growing integration of circular economy principles and stakeholder-driven commitments. However, it identifies a lack of standardized metrics and limited use of life cycle assessments as major constraints to effective policy evaluation. Overall, the findings demonstrate that plastic reduction strategies in Turkey are evolving into multidimensional value-creation tools that simultaneously support environmental sustainability, corporate reputation, and marketing performance.