CRIME AND DELINQUENCY PREVENTION IS AN EFFORT TO AVOID CONFLICTS OVER BEHAVIOR BETWEEN AN INDIVIDUAL AND A SOCIAL CONTROL AGENCY BY CHANGING THE PHYSICAL AND SOCIOECONOMIC ENVIRONMENT, THE PSYCHOLOGICAL OR BIOLOGICAL CHARACTERISTICS OF THE INDIVIDUAL, OR THE POLICY OF THE AGENCY AND THE LEGAL EVALUATION OF THE BEHAVIOR. EFFORTS AT CHANGING THE POTENTIAL OFFENDER ARE WIDELY RECOGNIZED AS INEFFECTIVE, ALTHOUGH THE SOCIAL SERVICES PROVIDED THROUGH DELINQUENCY PREVENTION PROGRAMS ARE OFTEN VALUABLE IN THEMSELVES. CHANGING THE ENVIRONMENT TO MAKE CRIME MORE DIFFICULT, SUCCESSFULLY IMPLEMENTED IN THE UNITED STATES THROUGH SECURITY SURVEYS AND IDENTIFICATION OF VALUABLES WITH TRACEABLE NUMBERS, AND DECRIMINALIZING VICTIMLESS ACTS IS REGARDED AS THE MOST PROMISING APPROACH TO CRIME PREVENTION. EVALUATION OF PROGRAMS IS DIFFICULT; SCIENTIFIC, PRACTICAL, AND POLITICAL CRITERIA MUST ALL BE IMPLEMENTED. NONEXPERIMENTAL DESIGNS ARE USED IN PROGRAM EVALUATION. CHOICE OF DESIGN WILL BE DETERMINED BY THE SPECIFIC CIRCUMSTANCES OF THE EVALUATION, PARTICULARLY THE AVAILABILITY OF RECORDS, DATA AND FUNDS. SUGGESTED DESIGNS INCLUDE QUASI-EXPERIMENTAL, TIME SERIES, REGRESSION DISCONTINUITY AND CORRELATIONAL. A NUMBER OF APPROACHES TO CRIME AND DELINQUENCY PREVENTION WERE OBSERVED IN EUROPEAN COUNTRIES INCLUDING FAMILY CASEWORK, ORGANIZATION OF LEISURE TIME ACTIVITIES, COMMUNITY ORGANIZATION TO IMPROVE COHESIVENESS, AND CRISIS INTERVENTION CENTERS. FEW EVALUATION STUDIES OF EUROPEAN PREVENTION PROGRAMS EXIST. PRIMARY PREVENTION EFFORTS SHOULD BE ENCOURAGED THROUGH COOPERATION BETWEEN POLICE AND INTERESTED ORGANIZATIONS. PREVENTION THROUGH ENVIRONMENTAL DESIGN, SUCH AS SECURITY-ORIENTED BUILDING CODES, IS ADVISED. CRIMINAL CODES SHOULD BE MODERNIZED, PARTICULARLY BY DECRIMINALIZING VICTIMLESS ACTS. SECONDARY PREVENTION PROGRAMS SHOULD BE THE RESPONSIBILITY OF PRIVATE ORGANIZATIONS. FURTHER RESEARCH INTO CRIME PREVENTION PROGRAM EFFECTIVENESS IS ENCOURAGED. FIGURES, TABLES, REFERENCES, AND AN APPENDIX OF SOME EUROPEAN DELINQUENCY PREVENTION PROJECT DESCRIPTIONS ARE INCLUDED IN THE REPORT. (AUTHOR ABSTRACT MODIFIED--LWM)