The regional security aspect is becoming increasingly more important within security studies. The United Nations and the United Nations Security Council has expressed an intent to utilize regional organizations as security actors with regards to maintaining international peace and security, with the purpose of achieving a greater sense of legitimacy for conflict resolution. This study aims to explore the possibilities of using such organizations within regions of varying stability, and how this usage can relate to the idea of legitimacy. Based on regional security complex theory, this study seeks to show how regional organizations have been used by the Security Council within different security sectors, and how this usage is affected by the degree of integration within the region. The result of the study show that the idea of legitimacy is easiest to achieve in regions with a mid-level degree of regional integration and concerning questions of political security. The results also show a tendency within the Security Council to use organizations from other regions with higher levels of integration in regions with lower levels of integration, and raises the question if this way of using regional organizations may risk harming the ultimate goal of legitimacy.