Under the Convention on Cluster Munitions, the obligation to clear cluster munition remnants is the responsibility of States that have jurisdiction or control over the affected area. This responsibility is coupled with an obligation to provide assistance for each State Party “in a position to do so.” In other words, clearance of cluster munition remnants is a collective responsibility. Collective responsibility may not, however, be implemented if not accompanied by adequate supervision; which States discharge collective responsibility concretely, as well as when and how it is discharged is open to interpretation, so it can easily be evaded or ignored. This article argues that: (1) the idea of collective responsibility for the clearance of cluster munition remnants in this convention is genuinely supported by the States Parties; and (2) this convention is equipped with a supervisory mechanism for the effective implementation of this collective responsibility. Supervision under the Convention on Cluster Munitions includes Meetings of States Parties, Review Conferences, intersessional meetings, and working groups for thematic discussions. The experience since the entry into force of the convention in 2010 shows that together they function as quasi-constant fora of monitoring, exchange of views, and persuasion. These supervisory mechanisms do not enforce the collective responsibility, but motivate States Parties to implement it.