The role and composition of the Standing Committee on Operational Cooperation on Internal Security (COSI) is explained in article 71 of the Treaty on the Functioning of the EU.
COSI facilitates, promotes and strengthens coordination of EU member states' operational actions related to the EU's internal security. It:
COSI consists of high-level officials from each EU member state's Ministry of Interior and/or Justice, as well as Commission and EEAS representatives. Europol, Eurojust, Frontex, CEPOL and other relevant bodies may be invited to attend the meeting as observers.