Evidence of organic psychological deficits in Vietnam veterans exposed to the herbicide Agent Orange was established through a neuropsychological battery. Also, the exposed Vietnam veterans, in contrast to a matched control group of Vietnam veterans, showed a significantly higher rate of posttraumatic stress disorder and its associated features: depression, anxiety, and increased aggression. The latter was subdivided into uncontrollable pressures, verbal violence, violence against objects, assaults, and suicidal thoughts. Active cases of chloracne, a medical indicator, were used to determine Agent Orange exposure.