The Central Office in Quezon City, built in 1971, is Iglesia ni Cristo's headquarters. The Central Office is one of several structures inside the INC Central Office Complex. It houses the permanent offices of the central administration and some of the church's departments. It is here where about a thousand INC professionals and volunteers hold office. It was located in Manila during its early years, then in San Juan, and later in Makati, before moving to its present site. INC also has three main offices outside the Philippines; in Burlingame, California; Washington D.C.; and in Heathrow, London.