A number of experiments conducted by the municipal police of Amsterdam, The Hague, Hooveveen, and Utrecht have been completed, and a provisional evaluation can be made. The experiments in Amsterdam, The Hague, and Hoogeveen emphasized police crime-specific prevention, with attention to burglary, vandalism, and theft. Uniformed patrol officers were principally involved, with a common element of the experiments being police presence in the streets in the form of foot patrols. In addition to the aforementioned experiments, Utrecht established a burglary detection project to investigate whether the introduction of more efficient and effective procedures in criminal investigation can help counter burglary and theft offenses. Although the experiments did not appear to reduce the targeted crimes significantly over the period examined, fear of crime was reduced while crime reporting increased. Public attitudes toward the police became more favorable, laying the foundation for improved police-citizen cooperation. One of the problems encountered was that of program content, centered around the relationship between police methods and the crime rate. Technical and methodological problems emerged in the implementation and evaluation of the experiments. These problems related to (1) the time period over which effects occur and can be measured, (2) how to measure the effects of the experiments, (3) the extent to which the public is aware of police action and experimental police methods, (4) the costs and benefits of the various projects, (5) the measurement of comparative effects, and (6) practical problems in implementation. Guidelines for further experiments are outlined.