This Brief sheds light on the motivation of humanitarian intervention from a theoretical and empirical point of view. An in-depth analysis of the theoretical arguments surrounding the issue of a legitimate motivation for humanitarian intervention demonstrate to what extent either altruism or national/self-interests are considered a righteous stimulus. The question about what constitutes a just intervention has been at the core of debates in Just War Theory for centuries. In particular in regards to humanitarian intervention it is oftentimes difficult to define the criteria for a righteous intervention. More than in conventional military interventions, the motivation and intention behind humanitarian intervention is a crucial factor. Whether the humanitarian intervention cases of the post-Cold War era were driven by altruistic or by self-interested considerations is a question is covered within and enables a comprehensive and holistic evaluation of the question of what motivates Western democracies to intervene or to abstain from intervention in humanitarian crises.

Introduction. - 1.The Legal and Moral Legitimacy of Intervention.- 1.1 The Impact of Globalization on the International State System.- 1.2. Intervention in International Law since 1945.- 1.3. The Ethics of Humanitarian Intervention.- 2. National Interests and Altruism in Humanitarian Intervention.- 2.1. Humanitarian Intervention and National Interest.- 2.2 Humanitarian Intervention and Altruism.- 3. The Motivation for Humanitarian Intervention.- 3.1. Research Design and Method.- 3.2. Case Analysis.- 4. Quantitative Analysis.- Conclusion.- Bibliography.