The Conference of the Parties (COP) is the decision-making organ of the Convention. It establishes and keeps under review the financial regulations of the Convention, adopts the budget for each financial period and reviews the implementation of the Convention. In particular, it may review and assess the conservation status of migratory species and the progress made towards their conservation; it provides guidance, receives reports and makes recommendations to the Parties.

The COP meets at intervals of not more than three years. So far, since the Convention entered into force in 1983, the COP has held nine conferences. The last CMS Conference of the Parties (COP9) took place in December 2008.