PATUXENT INSTITUTION WAS OPENED AS A MAXIMUM-SECURITY INSTITUTION FOR REPEAT ADULT OFFENDERS WHO BY DEMONSTRATION OF PERSISTENT AGGRAVATED AND ANTISOCIAL OR CRIMINAL BEHAVIOR EVIDENCED A PROPENSITY TOWARD CRIMINAL BEHAVIOR AND WHO, ON EVIDENCE OF STANDARD TESTS AND CLINICAL PROCEDURES, REVEAL EITHER INTELLECTUAL DEFICIENCY OR EMOTIONAL DISORDER. THE INSTITUTION'S PURPOSE WAS TO PROTECT SOCIETY FROM POTENTIALLY DANGEROUS OFFENDERS BY KEEPING THEM INCAPACITATED UNTIL THEY WERE NO LONGER DANGEROUS, AND TO PROVIDE A THERAPEUTIC ENVIRONMENT WHICH WOULD AID IN THEIR REHABILITATION. OFFENDERS WERE COMMITTED TO PATUXENT ON AN INDETERMINATE SENTENCE TO ENSURE THEY WOULD REMAIN THERE UNTIL THEY WERE EITHER NO LONGER DANGEROUS OR SUCCESSFULLY REHABILITATED. BASED ON A SCRUTINY OF BOTH THE THEORY AND THE PRACTICE BEHIND THE INSTITUTION, THE REPORT CONCLUDES THAT THE INDETERMINATE SENTENCE AND THE CONCEPT OF DEFECTIVE DELINQUENCY SHOULD BE REPEALED AND THAT THE PRESENT PROGRAM AT PATUXENT SHOULD BE SIGNIFICANTLY MODIFIED. PATUXENT SHOULD BE CONTINUED AS A SPECIAL PROGRAM FACILITY, BUT THE EXISTING PATUXENT PROGRAM SHOULD BE MODIFIED TO ALLOW FOR A RANGE OF PROGRAM ALTERNATIVES INDICATED TO BE APPROPRIATE AND EFFECTIVE FOR THE POPULATION BEING SERVED. AS AN INTEGRAL PART OF THE NEW PROGRAM, AN EFFECTIVE RESEARCH AND DEVELOPMENT EFFORT SHOULD BE ESTABLISHED TO EVALUATE AND RECOMMEND IMPROVEMENTS ON A CONTINUING BASIS. SUPPORTING DATA AND A BIBLIOGRAPHY ARE APPENDED. (AUTHOR ABSTRACT MODIFIED).