Third in a series of five congressionally mandated studies occurring biennially, this book is an updated review and evaluation of the available scientific evidence regarding the statistical association between exposure to herbicides used in Vietnam and various adverse health outcomes suspected to be linked with such exposures. As part of the review, the committee convened a workshop at which issues surrounding the reanalysis and the combination of existing data on the health effects of herbicide and dioxin exposure were addressed. This book builds upon the information developed by the IOM committees responsible for the 1994 original report, Veterans and Agent Orange , and Veterans and Agent Orange: Update 1996 , but will focus on scientific studies and other information developed since the release of these reports.The two previous volumes have noted that sufficient evidence exists to link soft tissue sarcoma, non-Hodgkin’s lymphoma, Hodgkin’s disease, and chloracne with exposure. The books also noted that there is ‘limited or suggestive’ evidence to show an association with exposure and a neurological disorder in veterans and with the congenital birth defect spina bifida in veterans’ children. This volume will be critically important to both policymakers and physicians in the federal government, Vietnam veterans and their families, veterans organizations, researchers, and health professionals.