The IAA (International Affairs Agency) Headquarters is a skyscraper in Grand Theft Auto V, located on San Andreas Ave in Pillbox Hill, Downtown Los Santos, next to the Federal Investigation Bureau building. It is based on the Two California Plaza building in Los Angeles, California, and is the IAA's field office for the state of San Andreas.
The IAA and FIB buildings are both government run agencies and are similar in design both in the interior and exterior of each skyscraper. The number of floors is unknown but the building most likely possess similar features of FIB building such as restricted and high security areas in the highest floors. The rest of the building is most likely composed of offices.
- For the actual mission walkthrough, see Three's Company
Part of the inside of the building is seen in the mission Three's Company, where Michael De Santa, Trevor Philips and Franklin Clinton are forced by FIB agent Steve Haines to perform an abduction against the IAA in order to boost the funding for the FIB. During the abduction, a former GTA IV character, Karen, is seen torturing and beating Ferdinand Karimov, which implies she is working for the agency as a lead interrogator.
- Only the floor where the break-in from the mission is seen; the rest of the building is inaccessible.