A psychologist is a doctoral level expert who has studied the science of how people think, feel and behave and applies this knowledge to help people understand, explain and change behavior. In the security clearance process, a psychologist functions as a consultant providing expert opinions about the meaning of historical and current information, symptom patterns, and behaviors and making predictions about the impact on an applicant’s reliability, trustworthiness, and judgment. Psychologists augment the security clearance decision making process with enhanced information adjudicators can use—in conjunction with all other available information—to make accurate clearance decisions.