The evaluation was conducted in four experimental and two comparison counties in New York State. The primary data set consisted of 3,692 felony arrests between 1983 and 1986. Results indicate that the program did improve the quality of felony convictions by enhancing coordination and communication between prosecutors and arresting officers. In the two counties where implementation was most successful, liaison was the sole duty of officers assigned to the prosecutors' offices. The major impact of liaison was in decreasing the probability of conviction on a lesser charge rather than affecting whether cases were won or lost. In both experimental and comparison counties, case attrition was not found to be a result of problems relating to case preparation or evidence collection. Failure to convict on the highest charge, rather, was due to the nature of the case, the defendant's prior record, or victim and witness problems. Results suggest that improved approaches to handling victims and witnesses could reduce case attrition. Worksheets and survey forms are appended. 8 references and 13 tables.