This chapter examines the role of transnational non-governmental organizations (TNGOs) in world politics. It considers what distinguishes TNGOs from other actors in international politics, what types of influence NGOs exert in international relations, and whether TNGOs contribute to more democratic policy-making at the international level. The chapter also discusses the growing importance of TNGOs and presents two case studies that illustrate how they contribute to the emergence of new norms through their engagement with international governmental organizations (IGOs), provide assistance to those in need, but also highlight the diversity that exists among the organizations. The first is about the adoption of United Nations Security Council resolution 1325 ‘Women, Peace, and Security’ to which TNGOs contributed in a significant manner, while the second is about the search and rescue missions of migrants which TNGOs undertake in the Mediterranean Sea. There is also an Opposing Opinions box that asks whether TNGOs contribute to more democracy at the international level.