In July 1990, the Los Angeles Police Department established the Threat Management Unit (TMU) to investigate long-term, abnormal patterns of threat and harassment directed toward a specific individual. The TMU's strategy involves both victim and suspect intervention. The victim is helped to address the stalking situation effectively through education, guidance in the development of self-protective behaviors, and the development of a therapeutic partnership with the victim designed to relieve extreme anxieties. After a comprehensive victim intervention operation is established, the investigating officer usually has a clear understanding of the nature of the case, the strength of the victim, and the type of obsessional conduct exhibited by the suspect. The type of suspect intervention pursued depends on the nature of the case. Options for suspect intervention are detective contacts with the suspect, temporary restraining orders, detentions and arrests, mental health diversions, criminal convictions, and possibly deportation. The evaluation of the TMU program involved an examination of all their cases initiated during the 18-month period from January 1, 1991, to June 30, 1992 (102 cases). Success was measured in terms of the degree of reduction in harassing and stalking behaviors over a 6- month period. The evaluation shows that an aggressive intervention policy can be effective in reducing or completely stopping harassing behavior toward a victim. 2 figures