The United Nations Security Council alone has the power, under chapter VII, to adopt binding resolutions concerning interventions in civil wars through peacekeeping missions. While some research has focused on the conditions under which such resolutions are adopted or rejected (most often due to a veto by a permanent member), we know little what influences whether such resolutions are introduced for consideration by the UNSC, or put differently, who sponsors such resolutions. This is problematic as the absence of an adopted resolution, for instance for creating a peacekeeping operation might be due to the absence of a sponsor for such a resolution or a negative vote on a resolution introduced. In part as a consequence, sponsorship decisions by the members of the UNSC are quite likely to be affected by the likelihood of winning approval by the fifteen members of the UNSC and the sponsorship decisions of other members. We propose an empirical approach that allows taking these interdependencies into account, and, when evaluating commonly used explanatory variables for the adoption of peacekeeping missions, we find results contradicting previous findings on the adoption of such resolutions.