The research objectives were to describe the tactics and techniques used by soldiers recognized as expert mine and boobytrap detectors and to discover the psychological, background, and Army experience contributing to their expertise. The study participants were those individuals named by peers and superiors as expert. The 78 men were given several tests and participated in an interview. Only two tests measuring the use of concepts were significantly related to rated expertise in detection, so most of the tests may not test for variables important to detection performance. Background information had no apparent relationship to expertise. It was concluded that identifying highly proficient detectors on the basis of non-experiential variables is not likely to be successful, but it may be possible to identify these individuals on the basis of experience-oriented data. (AG)