Most specialized technical workers are American or European,[22] and are occupied particularly in the defence and petrochemical industries.[2] Westerners generally feel that they are paid well and have excellent living conditions and housing with schooling paid for by their employers.[23] They often live in compounds or gated communities,[18] such as the Saudi Aramco compound at Dhahran Camp. However, many Westerners left the country in 2003 and 2004 following the terrorist attacks in Riyadh, Khobar and Yanbu.[23] A significant number of U.S. workers are English teachers.[24]