ABSTRACT
Several external factors, as well as internal demographic and cultural factors, are of primary importance in 'settling', 'civilizing' and 'globalizing' swiddeners. These include international politics, population growth and migration, competing interests in both Thai and international societies, tailoring highland products to local environments, development of markets for highland products, farm-to-market roads and some general or local technological factors. The most important Thai government and quasi-governmental activities in the highlands over the past 50 years began with national defence and control of infectious diseases. The Thai government did not recognize earlier land grants made to highland villages by northern Thai princes, nor did it recognize or register highlanders claims to personal or household plots of swidden land. Controls on the ability of highlanders to claim new farm land and the use of labour-saving chemicals and machinery are now widespread 'push factors' in the highlands, leading to large-scale migration to urban lowlands, especially of young adults.
