The CCB, abbreviated as the Civil Cooperation Bureau is Elysium's official defense program and authoritative party. Its purpose is to protect the integrity of Elysium's defense protocols and act as necessary under the authority of the Defense Secretary, Jessica Delacourt and Elysium's acting President to protect Elysium's airspace, territory, residences, and official citizens.
CCB is homed in a highly-advanced building on Elysium and makes use of wireless/satellite communication, satellite imaging, and remote control to maintain its authoritative power not only on Elysium but apparently Earth, as well. It appears in the movie that the CCB has extensive outreach of authority, being able to legally summon military force on any individual or any organized action they consider to be malicious, such as in the movie when Max da Costa and a team was tasked with stealing cranial data from John Carlyle.
Members of the CCB as seen in the movie also seem to be citizens of Elysium, or at the very least earn the benefits of Elysium's facilities, such as the Med-Bays. Known significant members in the movie include Agent Kruger and Defense Secretary Delacourt.