The following were the U.S. bases, installations, and facilities covered by the Panama Canal Treaty of 1977 and associated documents (Agreement in Implementation of Article IV of that Treaty) which entered into force October 1, 1979. Some were designated as Defense Sites while the others were designated Military Areas of Coordination (for housing, training, special facilities or General Military Areas of Coordination). Earlier inactive bases, installations, and facilities that had either been transferred to Panama under earlier agreements are not covered by this treaty. Those bases or facilities are covered in a related section, Description of U.S. Bases/Installations in Panama (1910-1999).

Defense Sites were those areas (and facilities within them) which Panama permitted the U.S. Forces to use for the specific purposes of the Panama Canal Treaty and as the two governments otherwise agreed. The Defense Sites were for the exclusive use of the U.S. Forces and were under their complete control for the life of the Panama Canal Treaty.

Military Areas of Coordination were those areas and facilities which Panama permitted the U.S. Forces to use for the purposes of communications and military training and for housing and support. With the exception of Special Facilities, their security was the combined responsibility of both countries; nevertheless, the senior U.S. Forces commander had ultimate responsibility for internal security of these forces (Map of the Panama Canal Area).