This chapter explores the crucial role of institutions and leaders in promoting sustainable development through the principles of the circular economy (CE). We analyze how institutional quality can act as a catalyst for change, creating an enabling environment for the adoption of sustainable practices. Additionally, the chapter examines the influence of lobbying, often perceived negatively, highlighting how it can be strategically leveraged to support policies and regulations that favor CE initiatives. Through case studies and theoretical frameworks, we investigate the strategies employed by leaders and organizations to shape policymaking in favor of sustainability, shedding light on both successes and potential challenges. Our goal is to provide a comprehensive understanding of the mechanisms through which institutions and lobbying efforts can work together to accelerate the transition towards sustainable development. The chapter concludes with practical recommendations for policymakers and leaders on strengthening institutional frameworks and effectively utilizing lobbying to achieve long-term sustainability goals.