Thai government policies for highland development are creating serious problems for ethnic hill tribes, among them environmental pollution, prostitution, AIDS, increasing opium addiction, and social disruption. Three questionable assumptions underlie government policies. Concern for opium eradication not only directs attention and funds away from groups who do not produce opium but has also failed, thus far, to find substitute crops that do not require extensive use of polluting chemical fertilizers and pesticides. The flawed assumption that shifting cultivators, rather than logging concerns, are major destroyers of the forests has led to fruitless efforts to relocate hill peoples. And the questionable theory that ethnic peoples pose a threat to national security has led to educational efforts that undermine traditional forms of village authority.