This chapter reviews the critical role that institutions play in environmental rule of law and the key opportunities for building more effective environmental institutions. In particular, the chapter highlights the need for clear and appropriate mandates; coordinating across sectors and levels of government; developing the capacity of institutions and personnel; collecting, using, and disseminating reliable data; employing independent audit and review mechanisms; ensuring the fair and consistent enforcement of law; and deploying leadership and management skills to empower staff and model behavior. This chapter concludes that with the proper mix of capacity, accountability, resources, integrity, and leadership, environmental institutions are poised to greatly narrow the implementation gap in the environmental rule of law.