Data were collected from questionnaires completed from 153 jurisdictions whose law enforcement departments had 150 or more officers. Over 25 agencies were then selected for more detailed study. The results of the study are presented in three volumes; this volume includes a summary and discusses policy implications. The study found that differences in investigative training, staffing, and procedures had little effect on crime, arrest, or clearance rates. The method by which police investigators were organized was also not related to variations in crime, arrest, and clearance rates. The most important determinant of a successful investigation was the information supplied by the victim to the immediately responding patrol officer. Routine police procedures often led to the clearance of crimes in which the perpetrator was not immediately identifiable at the beginning of the investigation. While investigators often collected from physical evidence than could be productively analyzed, latent fingerprints were rarely the only basis upon which a suspect was identified. Police failure to document a case investigation thoroughly can contribute to a higher case dismissal rate. The researchers made several recommendations designed to save resources and lead to a greater number of arrests and successful prosecutions. Chapter references