International Union for Conservation of Nature (IUCN) is the world’s oldest and largest global environmental network - a democratic membership union with more than 1,200 government and NGO member organizations, and almost 11,000 volunteer scientists in more than 160 countries. IUCN’s work is supported by over 1,000 professional staff in 60 offices and hundreds of partners in public, NGO and private sectors around the world.
However, IUCN initially re-opening its Liaison Project Office through and housed with UNESCO in 1992 and later on have its own Project Office in Phnom Penh till now.