Vietnam veterans with post-traumatic stress disorder (n = 11) and two other groups of Vietnam veterans (n = 24) instructed to fabricate symptoms of post-traumatic stress disorder completed the MMPI. A discriminant function analysis that used scale F and the post-traumatic stress disorder subscale correctly classified 91% of the subjects. This systematic replication supports the utility of the MMPI as a component in evaluating the validity of self-reported symptoms of post-traumatic stress disorder in Vietnam veterans.