Initially, the main influx was composed of Arab and Western technical, professional and administrative personnel, but subsequently substantial numbers came from Southeast Asia. Saudi Arabia has become increasingly dependent on foreign labour, and although foreign workers remain present in technical positions, most are now employed in the agriculture, cleaning and domestic service industries. The hierarchy of foreign workers is often dependent on their country of origin; workers from Arab nations and western nations generally hold the highest positions not held by Saudis, and the lower positions are occupied by persons from Africa, and Southeast Asia.