IN THE FIRST STUDY, PERFORMANCE ON THE MINNESOTA MULTIPHASIC PERSONALITY INVENTORY WAS USED TO DIVIDED THE SUBJECTS INTO FOUR GROUPS. THE TEST IDENTIFIED 58 LOW-ANXIOUS (PRIMARY) SOCIOPATHS, 38 HIGH-ANXIOUS (SECONDARY) SOCIOPATHS, 26 LOW-ANXIOUS NONSOCIOPATHS, AND 52 HIGH-ANXIOUS NONSOCIOPATHS. THE PRISON'S INCIDENCE REPORTS WERE THEN EXAMINED FOR EACH GROUP. THE PRIMARY SOCIOPATHS HAD A MEDIAN OF 3 INCIDENTS AND 2 DAYS OF SEGREGATION FOR SECONDARY SOCIOPATHS. THE FIGURES FOR NONSOCIOPATHS CLUSTERED AROUND ONE INCIDENT OR NO INCIDENTS REPORTED AND 6.3 SEGREGATION DAYS PER INCIDENT, COMPARED TO 2 INCIDENTS, AT ALL. THE SECOND STUDY, AN ATTEMPT TO REPLICATE THE FIRST, IDENTIFIED 26 PRIMARY SOCIOPATHS AND 21 SECONDARY SOCIOPATHS. IN THIS STUDY, PRIMARY SOCIOPATHS HAD A MEDIAN OF 3 INCIDENTS AND 8.4 DAYS SEGREGATION PER INCIDENT REPORT COMPARED TO 2 INCIDENTS AND 4 DAYS SEGREGATION FOR SECONDARY SOCIOPATHS. THESE FINDINGS ADD CREDENCE TO THE DISTINCTION BETWEEN PRIMARY AND SECONDARY SOCIOPATHY AND BRIDGE THE GAP BETWEEN STRICTLY EXPERIMENTAL LABORATORY INVESTIGATIONS WITH NONCRIMINAL POPULATIONS AND REALISTIC SITUATIONS. A BIBLIOGRAPHY IS APPENDED.