This chapter aims to give an overall picture of humanitarian intervention as a contested phenomenon. It provides a description of the roots of the phenomenon by giving a historical introduction using significant examples. The chapter outlines reform initiatives to the idea of intervention and analyses the main debates to better understand the situation in the literature. In the 1990s, the number of humanitarian interventions increased abruptly. Most of these interventions were conducted or initiated by the UN encountering both successes and failures. The biggest debate on humanitarian intervention focuses on which circumstances can justify a coercive intervention. Human security, freedom, rule of law, human rights, and good governance represent a normative discourse to legitimize interventionism which is often deployed to support states’ self-interested motivations. Global governance is shaped by different organizations, nongovernmental organizations, interest groups, global society, and other authorities having regulatory tasks.