Experiments in Kansas City, St. Louis, and Minneapolis showed the crime rate was not affected by random police patrol. A second study in Kansas City revealed that police response time was unrelated to the probability of making an arrest or locating a witness. These findings suggest that police resources could be better used in other activities. Some police strategies proven effective in reducing citizens' fear of crime and increasing their sense of security are the use of police minicenters in some neighborhoods, police door-to-door contacts with residents to identify local problems, and the use of police officers to help organize neighborhood crime prevention efforts. The use of a differential response scheme to respond to citizen calls for police service has freed police for additional tasks without compromising citizen security or satisfaction with police. Research in Newport News, Va., has shown the value of problem-oriented policing, which is based in crime analysis followed by the implementation of a plan to deal with significant crime problems.