RECENT STUDIES ON SUBJECTIVE MEASURES OF DETERRENCE ARE FIRST DESCRIBED. METHODOLOGY OF THE CURRENT STUDY IS THEN OUTLINED. QUESTIONNAIRE AND INTERVIEW RESPONSES OF 302 SECONDARY SCHOOL STUDENTS, 74 YOUTHS FREQUENTING INNER-CITY DROP-IN CENTERS, AND 20 RESIDENTS AT A BOYS AND GIRLS TREATMENT CENTER WERE ANALYZED. THE INTERVIEWS AND QUESTIONNAIRES SOLICITED INFORMATION ON THE YOUTHS PERCEPTIONS OF PUNISHMENT AND THEIR PERSONAL HISTORIES OF VARIOUS FORMS OF DEVIANCE. IT WAS HYPOTHESIZED THAT THOSE RESPONDENTS WHO PERCEIVE A HIGHER CERTAINTY OF PUNISHMENT SHOULD ENGAGE IN LESS DEVIANCE; THAT THOSE RESPONDENTS WHO PERCEIVE A HIGHER SEVERITY OF PUNISHMENT AND A HIGH CERTAINTY (THOSE TO WHOM SEVERITY IS SALIENT) SHOULD ENGAGE IN LESS DEVIANCE; AND THAT THE EFFECTS SHOULD BE STRONGER FOR MALA PROHIBITA PERCEIVERS THAN FOR MALA IN SE PERCEIVERS. THE RESULTS SHOWED THAT OVER ALL CRIMES, ACROSS GROUPS, AND USING SEVERAL MEASURES OF DETERRENCE, CERTAINTY OF PUNISHMENT IS MORE IMPORTANT AS A DETERRENT THAN SEVERITY OF PUNISHMENT. THUS, FROM A DETERRENCE PERSPECTIVE, IN ORDER TO DECREASE CRIME ONE SHOULD INCREASE THE CERTAINTY OF PUNISHMENT. WEAK SUPPORT FOR THE FIRST AND SECOND HYPOTHESES WAS THUS FOUND. FINALLY, IT WAS NOTED THAT ASPECTS OF PUNISHMENT OTHER THAN JAIL ARE DETERRENTS TO SOME OF THE YOUTHS. ...DMC