Controlling the US Cocaine Epidemic: Prevention from Light vs. Treatment of Heavy Use + Doris A. Behrens Vienna University of Technology Department of Operations Research and Systems Theory Jonathan P. Caulkins ° Carnegie Mellon University H. John Heinz III School of Public Policy and Management and RAND Drug Policy Research Center Gernot Tragler and Gustav Feichtinger * Vienna University of Technology Department of Operations Research and Systems Theory Abstract: Since drug use and related problems substantially change over time, it seem plausible that drug interventions should vary too. Static interventions applied to a dynamic proc- ess may be counter-productive. Therefore we formulate the choice between treatment and prevention spending in the framework of dynamic optimal control. Prevention is the most appropriate control policy when there are relatively few heavy users, i.e. in the beginning of an epidemic. Treatment, however, is most sufficient to support the de- cline of drug abuse optimally. Additionally these models are able to generate a number of interesting insights, among which are (1) costs of interventions as well as social cost associated with the quantity consumed increase with the delays in the starting year of control, (2) people who perceive drug use to be costly for society should favor greater drug control spending per gram consumed and allocate a grater proportion of that spending to prevention. + This research was partly financed by the Austrian Science Foundation under contract No. P11711-SOZ („Dynamics of Law Enforcement“), the National Consortium on Violence Re- search, and by the US National Science Foundation under Grant No. SBR-9357936. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation ° 5000 Forbes Ave., Pittsburgh, PA 15213; email: caulkins+@andrew.cmu.edu * corresponding author: Argentinierstraße 8/119, A-1040 Vienna, Austria; email: or@e119ws1.tuwien.ac.at