Set up in May 1948, UNTSO was the first ever peacekeeping operation established by the United Nations. Since then, UNTSO military observers have remained in the Middle East to monitor ceasefires, supervise armistice agreements, prevent isolated incidents from escalating and assist other UN peacekeeping operations in the region to fulfil their respective mandates.

UNTSO personnel have also been available at short notice to form the nucleus of some other peacekeeping operations worldwide. The ability of UNTSO's military observers to deploy almost immediately after the Security Council has authorized  a new mission, has been a significant factor in the success of those operations.