THE HOSPITAL WAS SURVEYED FOR ADMISSIONS FROM FEBRUARY 1971 TO OCTOBER 1974. THE SEX OFFENDER WAS DEFINED AS A PATIENT WHOSE ADMISSION TO RAMPTON HOSPITAL WAS A DIRECT RESULT OF A CONVICTION FOR A SEXUAL CRIME. INFORMATION SUPPLIED BY RAMPTON'S PSYCHOLOGY DEPARTMENT, WHICH HAD TESTED ALL NEW ADMISSIONS SINCE FEBRUARY 1971, WAS ALSO USED. THIS OVERSIMPLIFIED SURVEY WAS NECESSITATED BY TIME LIMITATIONS OF THE STUDY. OF RAMPTON HOSPITAL'S MALE PATIENTS, 18.4 PERCENT WERE ADMITTED AS A DIRECT RESULT OF A CONVICTION FOR A SEXUAL OFFENSE, BUT NEARLY 30 PERCENT OF THE OVERALL RESIDENT SEXUAL OFFENDER POPULATION COULD BE SO CLASSIFIED. THE SEXUAL OFFENDERS' AVERAGE AGE WAS 25.9 YEARS (27.5 YEARS FOR RESIDENTS) WITH A RANGE OF 17-34 YEARS (18-36 FOR RESIDENTS), AND THE VAST MAJORITY (AROUND 90 PERCENT) WERE SINGLE AT THE TIME OF ADMISSION. ONLY A MINORITY HAD NO PREVIOUS CONVICTIONS FOR BOTH SEXUAL AND NONSEXUAL OFFENSES. MENTAL HEALTH CLASSIFICATIONS SHOWED THE BULK TO BE CLASSIFIED EITHER AS PSYCHOPATHIC DISORDER OR SUBNORMALITY. THESE TWO DIAGNOSTIC CATEGORIES ARE LEGAL AND ADMINISTRATIVE METHODS OF DETAINING PATIENTS, AND THEY ARE INTERCHANGEABLE. OF THE VICTIMS, 69 PERCENT WERE FEMALE AND 20.5 PERCENT MALE. THE OFFENSES HAD BEEN COMMITTED AGAINST A PARTICULAR TYPE OF VICTIM CLASSIFIED ACCORDING TO AGE AND SEX. NO EVIDENCE WAS FOUND OF ANY ASSOCIATION BETWEEN CHROMOSOME ABNORMALITY AND DESIGNATION AS A SEX OFFENDER NOR BETWEEN INTELLIGENCE AND DESIGNATION AS A SEX OFFENDER. EXTENSIVE TABLES SUPPLEMENT THE TEXT. (AUTHOR ABSTRACT MODIFIED)