Due to the U.S.-led bombing campaign in 2001–2002 carried out against the Taliban regime, a large Afghan refugee population was created in surrounding countries. The Afghan refugee population in Pakistan in 2002 was approximately 3.7 million, and, in Iran and the west, an additional 1.6 million. In 2002, there were approximately 1 million internally displaced persons (IDP) within the country. Since early-2002, there were many spontaneous returnees, but the UN High Commissioner for Refugees (UNHCR) began assisting refugees to repatriate in February 2002. As of October, more than over 1.5 million had returned to their homes.
In mid-2002, there was a daily influx of homeless migrants into Kabul, approximately 300–400 families a day. Seventy percent of Kabul's population was living in illegal structures.
In the summer of 2001, the majority of the over 1 million internally displaced persons in Afghanistan had been driven off their land and into refugee camps by ongoing conflict and four years of drought. After September 11, 2001, the International Organization for Migration (IOM) began to deliver shelter and non-food supplies to help the IDPs survive the Afghan winter. It dispatched road convoys from Iran, Tajikistan, and Turkmenistan to destinations in Afghanistan, carrying blankets, winter clothing, tents, and other essential items. Following the winter, with the defeat of the Taliban and the beginning of the spring planting season, the IOM worked to return the IDPs to their villages from the refugee camps. The IDP families were offered wheat, seeds, blankets, soap, agricultural tools, and other items. In addition to the IOM and the UNHCR, the International Committee of the Red Cross and UNICEF have been heavily involved in repatriating refugees.
Underway in the country is also the Return of Qualified Afghans program, designed to bring back Afghan professionals living abroad to participate in rebuilding the country. The program had returned 227 people by mid-2002. A further 343 people were identified to fill key jobs in ministries and nongovernmental organizations (NGOs).