The Vietnam war of 1961-1975 is, among other things, notable for the massive employment of anti-plant chemical warfare agents (herbicides or plant defoliating and killing chemicals). Primarily during the mid to late 1960's the USA sprayed approximately 72 million liters of these herbicides over some 1.7 million hectares of rural South Vietnam; that is about one hectare in every ten. At least 12% of the forests of South Vietnam were sprayed one or more times as were 5% or more of the agricultural land.The "International Symposium on Herbicides and Defoliants in War: The Long-term Effects of Man and Nature" was convened in Ho Chi Minh City from January 14 to 19, 1983 in order to examine the aftermath of this chemical assault on South Vietnam, after about a decade had elapsed since the spraying. More than 70 ecological and medical scientists from some 20 countries, both East and West, came together in order to meet with about an equal number of their Vietnamese counterparts. The international participants included some of the top experts in the world in their respective fields of ecological and medical science. It was strictly a working conference open only to qualified scientists.This is the final summary report of the symposium and the seven final summary reports of the various working groups, plus an article compiled from papers presented by participating Vietnamese scientists.