BELIEF IN THE DETERRENT EFFICACY OF PENAL SANCTIONS IS AS OLD AS CRIMINAL LAW ITSELF. UNTIL QUITE RECENTLY, HOWEVER, DISCUSSION OF PUNISHMENT IN GENERAL AND DETERRENCE IN PARTICULAR HAS BEEN IN THE MAIN QUITE UNSCIENTIFIC. THE AUTHORS ESTABLISH A CONCEPTUAL AND PHILOSOPHIC BASIS FOR THE FURTHER STUDY OF DETERRENCE AND DEFINE A STRATEGY OF RESEARCH TO THAT END. THEY ARGUE THAT TIME AND EFFORT ARE WASTED IN THE GENERAL DEBATE ABOUT WHETHER PUNISHMENT DETERS CRIME. IT IS MUCH MORE IMPORTANT, THEY CONTEND, TO INVESTIGATE THE GREAT VARIETY OF FACTORS WHICH CONDITION THE DIFFERENTIAL EFFECTS OF LEGAL THREATS. THE AUTHORS THEN DISCUSS THE DIFFERENCES AMONG MEN, DIFFERENCES AMONG TYPES OF CRIME, THE VARIOUS WAYS THAT LEGAL THREATS ARE COMMUNICATED, VARIATIONS IN PENALTY AND IN RISK OF PENALTY, AND OTHER FACTORS THAT HELP TO EXPLAIN WHY SOME LEGAL THREATS FAIL AND OTHERS SUCCEED. FINALLY, THEY CONSIDER THE METHODS BY WHICH WE CAN COMPARE THE EFFECTS OF LEGAL THREATS AND PROPOSE A NUMBER OF AREAS FOR FURTHER RESEARCH. (PUBLISHER ABSTRACT) (SNI ABSTRACT)