Headquarters of the United Nations However, the UN did reject an unusual "model playground" proposal for that site, instead choosing to construct a play area similar to others found around New York City. The first 450 UN employees started working at the Secretariat Building on August 22, 1950. The United Nations officially moved into the Secretariat Building on January 8, 1951, by which time 3,300 employees occupied the building. At the time, much of the Secretariat Building was still unfinished, and the bulk of the UN's operations still remained at Lake Success. A centralized phone-communications system, was built to facilitate communications within the complex. The
Headquarters of the United Nations UN Plaza) are also part of headquarters. In addition, the Church Center for the United Nations (777 UN Plaza) is a private building owned by the United Methodist Church as an interfaith space housing the offices of several non-governmental organizations. The Office of Internal Oversight Services (OIOS) is located at 380 Madison Avenue. In October 2011 city and state officials announced an agreement in which the UN would be allowed to build a long-sought new office tower adjacent to the existing campus on the current Robert Moses Playground, which would be relocated. In exchange, the United Nations would allow the