THE PSYCHOLOGICAL MOTIVATION OF THE RAPIST IS DISCUSSED IN TERMS OF THE WAYS IN WHICH AGGRESSIVE AND SEXUAL COMPONENTS OF HIS PERSONALITY MAY BE RELATED. RAPE SEEN AS PREVERSION, SADISM, HOSTILITY, AND DOMINATION IS TREATED; A COMBINATION OF FACTORS IS THOUGHT TO MOTIVATE RAPISTS. PSYCHOMETRIC TESTS HAVE BEEN USED TO STUDY THE DYNAMICS OF RAPE, INCLUDING THE RORSCHACH TEST, THE THEMATIC APPERCEPTION TEST, THE HOUSE-TREE-PERSON TEST, THE BLACKY TEST, THE MINNESOTA MULTIPHASIC PERSONALITY INVENTORY, THE SEX INVENTORY, THE EDWARDS PERSONAL PREFERENCE SCHEDULE, THE BUSS-DURKEE HOSTILITY INVENTORY, AND THE MEGARGEE OVER-CONTROLLED HOSTILITY RATING SCALE. ALTHOUGH REPORTS OF SUCH TESTS ON RAPISTS ARE FEW, DATA ARE INCONSISTENT, AND ADEQUATE CONTROL GROUPS HAVE NOT BEEN STUDIED, IT IS POINTED OUT THAT PSYCHOMETRIC TESTING IS USEFUL IN INDIVIDUAL CASES AND IN AIDING THE PSYCHIATRIST WHO MUST TESTIFY IN COURT REGARDING THE DIAGNOSIS AND DISPOSITION OF A RAPIST. PSYCHODYNAMIC AND PSYCHOGENETIC FACTORS IN THE HISTORY OF THE RAPIST, SUCH AS CHILDHOOD DEVELOPMENT, PARENTAL SEDUCTION, PARENTAL CRUELTY, PARENTAL ABSENCE OR LACK OF INVOLVEMENT, POSITIVE PARENTAL RELATIONSHIP, LATENCY AGE DEVELOPMENT, AND ADOLESCENCE, ARE EXAMINED. THE LITERATURE SUGGESTS THAT PARENTAL REJECTION, DOMINATION, CRUELTY, AND SEXUAL SEDUCTION OR OVERSTIMULATION ARE IMPORTANT FACTORS IN THE EARLY LIFE EXPERIENCES OF THE RAPIST. HOWEVER, THERE IS NO EVIDENCE THAT EARLY BEHAVIOR DISTURBANCE IS PREDICTIVE OF EVENTUAL RAPE ACTIVITY. THE PSYCHODYNAMICS OF SPECIFIC RAPE OFFENSES ARE VIEWED FROM THE PERSPECTIVES OF RAPE AS A DEFENSE AGAINST FEELINGS OF SEXUAL INADEQUACY, AS A DEFENSE AGAINST DEPENDENCY NEEDS, AS A DISPLACEMENT OF HOSTILITY INTO THE VICTIM, AS A DEFENSE AGAINST HOMOSEXUAL WISHES, AND A SYMPTOM OF A MADONNA-PROSTITUTE COMPLEX. ISSUES OF INTEREST TO MENTAL HEALTH AND LEGAL PROFESSIONALS ARE DISCUSSED, INCLUDING INTELLIGENCE, PHYSICAL CHARACTERISTICS, DREAMS, IMPOTENCE, WIVES OF RAPISTS, ALCOHOL AND OTHER DRUGS, RAPE-MURDER VERSUS LUST-MURDER, AND PROGRESSION FROM LESS SERIOUS TO MORE SERIOUS OFFENSES. REFERENCES ARE PROVIDED. (DAS)