Site Two Refugee Camp (also known as Site II or Site 2) was the largest refugee camp on the Thai-Cambodian border and, for several years, the largest refugee camp in Southeast Asia. The camp was established in January 1985 during the 1984-1985 Vietnamese dry-season offensive against guerrilla forces opposing Vietnam's occupation of Cambodia
In early 1985 the Royal Thai Government, together with the United Nations Border Relief Operation (UNBRO) and other UN agencies, decided to resettle populations displaced from refugee camps that had been destroyed by military activity into a single camp where aid agencies could provide combined services. Site Two was located in Thailand 70 kilometers northeast of Aranyaprathet, near Ta Phraya, approximately 4 kilometers from the Cambodian border.
The camp covered 7.5 square kilometres (2.9 sq mi) and combined the populations of Nong Samet (Rithysen), Bang Poo (Bang Phu), Nong Chan, Nam Yeun (a camp located on the eastern Thai-Cambodian border, near Laos), Sanro (Sanro Changan), O'Bok, Ban Sangae (Ampil), and Dang Rek (Dong Ruk)camps all of which had been displaced by fighting between November of 1984 and March of 1985. These camps supported the non-communist resistance spearheaded by Son Sann's Khmer People's National Liberation Front (KPNLF)., however Site Two was intended as a civilian camp and the KPNLAF forces were based in other locations.
One section of the camp was reserved for Vietnamese refugees and as of January 1988 Thailand transferred Vietnamese boat people directly to Site Two
Between 1989 and 1991 the camp's population went from 145,000 to over 198,000.
Initially programs at Site Two were limited to the most basic support services: medical care, public health programs, sanitation, construction, and skills training in areas directly related to the running of the camp. This was in keeping with the Thai policy of "humane deterrence": the principle that the camps should not become permanent settlements or provide a level of assistance beyond what the refugees could expect to find in Cambodia
Camp services were mostly provided by the American Refugee Committee (ARC), Catholic Office for Emergency Relief and Refugees (COERR), Concern, Christian Outreach (COR), Handicap International, the International Rescue Committee, Catholic Relief Services (CRS), the Japan International Volunteer Center (JVC), Malteser-Hilfsdienst Auslandsdienst (MHD), MSF, Operation Handicap International (OHI), the International Rescue Committee (IRC), Japan Sotoshu Relief Committee (JSRC), and YWAM. These organizations were coordinated by UNBRO, which was directly responsible for the distribution of food and water.