FOLLOWING A GENERAL DISCUSSION OF BUILDING MODELS AND USING THEM FOR ANALYTIC PURPOSES, SPECIFIC APPLICATIONS OF MODELS ARE DISCUSSED. LAW ENFORCEMENT AND POLICE OPERATIONS ARE EXAMINED FOR COMMUNITY VARIABLES IN CRIME CONTROL AND COST-EFFECTIVE MEANS OF POLICE DEPLOYMENT. THE JUDICIAL PROCESS IS ANALYZED TO DETERMINE SIZE OF JURY MOST EFFECTIVE, THE JURY DECISONMAKING PROCESS, AND RULES AND LOGIC OF DECISIONS. OPERATIONS RESEARCH AS APPLIED TO COURTS IS ALSO EXAMINED. THE COSTS OF VARIOUS CORRECTIONS ALTERNATIVES, CRIME DETERRENCE THROUGH CHOOSING THE PROPER SENTENCE, AND REDUCING RULE VIOLATION BY POLICE, JUDGES, AND CORRECTIONS OFFICIALS WHEN NEW PROCEDURES ARE INSTITUTED ARE EXAMINED THROUGH MODELS. MOST OF THE PAPERS PROVIDE REFERENCES.