DURING THE SUMMER OF 1979, A RAPE LED TO THE CONSTRUCTION OF A PSYCHOLOGICAL PROFILE BY THE FBI ACADEMY'S BEHAVIORAL SCIENCE UNIT. THREE DAYS AFTER RECEIVING THE PROFILE, THE REQUESTING AGENCY DEVELOPED APPROXIMATELY 40 NEIGHBORHOOD SUSPECTS. USING ADDITIONAL PROFILE INFORMATION, THEY NARROWED THEIR INVESTIGATION TO ONE PERSON WHO WAS ARRESTED WITHIN THE WEEK. PROFILES ARE BASED ON THE PSYCHOLOGICAL ASSESSMENT OF A CRIME SCENE WHERE CERTAIN ITEMS OF EVIDENCE ARE IDENTIFIED AND INTERPRETED TO INDICATE THE PERSONALITY TYPE OF THE INDIVIDUAL OR INDIVIDUALS COMMITTING THE CRIME. THE PROFILE ENABLES INVESTIGATORS TO LIMIT OR BETTER DIRECT THEIR INVESTIGATIONS BUT DOES NOT REPLACE SOUND INVESTIGATIVE PROCEDURES. PROFILING, DEVELOPED AS EARLY AS WORLD WAR II, WORKS IN HARMONY WITH THE SEARCH FOR PHYSICAL EVIDENCE. IT DERVICES FROM CURRENT BEHAVIORAL SCIENCE PRINCIPLES AND ASSUMES THAT A CRIME, PARTICULARLY A BIZARRE CRIME REFLECTS THE PERSONALITY CHARACTERISTICS OF THE PERPETRATOR. NECESSARY ITEMS FOR A PROFILE INCLUDE THE SURVIVING VICTIM'S RECONSTRUCTION OF EXACT CONVERSATIONS WITH THE PERPETRATOR, CRIME SCENE PHOTOGRAPHS, COMPLETED AUTOPSY PROTOCOL, AND A COMPLETE INCIDENT REPORT. IN ADDITION, THE PROFILER SEARCHES FOR THE MOTIVE AS PRIMARY PSYCHOLOGICAL EVIDENCE. PROFILES SHOULD BE CONFINED CHIEFLY TO CRIMES AGAINST THE PERSON WHERE THE MOTIVE IS LACKING AND WHERE EVIDENCE OF PSYCHOPATHOLOGY AT THE CRIME SCENE EXISTS. AN AGENCY REQUESTING A PSYCHOLOGICAL PROFILE SHOULD CONTACT THE FBI FIELD OFFICE WITHIN THE DEPARTMENT TERRITORY. FOOTNOTES ARE GIVEN. (AOP)