This chapter investigates the role of open data in supporting environmentally sustainable decision-making within corporate contexts. Through a conceptual analysis and two illustrative case studies—Ecolab and Patagonia—the chapter examines how open data practices, both in the form of data sharing and data receiving, can contribute to reducing environmental impacts. The findings highlight the potential of open data to enhance transparency, accountability, supply chain sustainability, and cross-sector collaboration. Building on these insights, the chapter proposes an integrated conceptual model that illustrates the mechanisms through which open data can support environmental impact mitigation. Avenues for future research are also discussed, with particular attention to the need for longitudinal analyses, sector-specific assessments, and the potential contributions of emerging technologies such as blockchain and artificial intelligence. Overall, the chapter contributes to the growing body of literature on data-driven sustainability and underscores the strategic relevance of open data for environmentally responsible business practices.