This fascinating series of letters again confirms that there is much illness among the veterans who served our nation in the Persian Gulf War. Dr Amato and colleagues, Dr Gots and colleagues, Dr Engel and colleagues, and Drs Hyams and Wignall present a beautifully incisive methodological dialogue that underscores the difficulties of drawing overly broad conclusions from small and highly selected populations.1-3 Also, these authors emphasize the difficulty of reconstructing exposure scenarios from self-reported data and stress the importance of using appropriate, state-of-the-art, objective instruments in the evaluation of subtle neuropsychological dysfunction. Dr Gordon and Dr Kaires illustrate the continuing difficulty that many Americans, physicians among them, have in accepting the notion that stress can cause disease. This reluctance is a serious impediment to the proper management of patients with stress-related illness and also impedes muchneeded research to better delineate associations between stress and a wide range of illnesses