Humanitarian intervention (HI) became a prominent feature of International Relations (IR) in the aftermath of the Cold War, and it set up the basis of what later developed as the Responsibility to Protect (R2P). From an International Relations perspective, the underlying debate developed around the questionof was what provided the humanitarian character of an intervention. In that regard, little attention was paid to the role of self-interest in the decision-making processes leading to such interventions. This paper asks what are the crucial factors that explain when humanitarian emergencies actually lead to humanitarian interventions. It builds upon the frameworks developed by Snyder, Bruck and Sapin (1962), and Rosenau (1966), which categorize five sources of influence in foreign policy decision making external or global, societal, governmental, individual and role sources— to analyze an emblematic case of HI in the history of international relations, namely, the Australian-led intervention in East Timor. First, the paper looks at the theoretical explanations of HI. Secondly, the debate about the configuration of self-interest is reviewed. Next, the paper identifies the role that different sources played in the process that lead to hi. Finally, the decision making framework is applied to Australia’s intervention in East Timor. Humanitarian intervention (HI) became a prominent feature of International Relations (IR) in the aftermath of the Cold War, and it set up the basis of what later developed as the Responsibility to Protect (R2P). From an International Relations perspective, the underlying debate developed around the question of was what provided the humanitarian character of an intervention. In that regard, little attention was paid to the role of self-interest in the decision-making processes leading to such interventions. This paper asks what are the crucial factors that explain when humanitarian emergencies actually lead to humanitarian interventions. It builds upon the frameworks developed by Snyder, Bruck and Sapin (1962), and Rosenau (1966), which categorize five sources of influence in foreign policy decision making —external or global, societal, governmental, individual and role sources— to analyze an emblematic case of hi in the history of international relations, namely, the Australian-led intervention in East Timor. First, the paper looks at the theoretical explanations of HI. Secondly, the debate about the configuration of self-interest is reviewed. Next, the paper identifies the role that different sources played in the process that lead to HI. Finally, the decision making framework is applied to Australia’s intervention in East Timor.Más allá de las buenas intenciones. El papel del interés nacional en las intervenciones humanitarias. Una mirada a la intervención australiana en Timor Oriental.La intervención humanitaria (IH) fue una de las figuras más recurrentes en las relaciones internacionales (RI) después de la Guerra Fría, y sentó las bases para lo que después se denominó la responsabilidad de proteger (R2P). Desde la perspectiva de las RI, el debate se centró en torno a la pregunta sobre ¿qué proveía el carácter humanitario de una intervención? Sin embargo, se prestó poca atención al papel del interés nacional en el proceso de toma de decisiones del cual emanaban dichas intervenciones. En este artículo se investiga qué factores son relevantes para explicar cuándo las emergencias humanitarias detonan intervenciones humanitarias. Se construye un análisis basado en el marco de toma de decisiones desarrollado por Snyder, Bruck y Sapin (1962), y Rosenau (1966), que propone cinco categorías que agrupan las fuentes de influencia que inciden en el proceso de toma de decisiones de la política exterior —externa o global, social, gubernamental, individual y el papel desempeñado por individuos— para analizar un caso de IH emblemático: la intervención liderada por Australia en Timor Oriental.