THE BOSTON, MASSACHUSETTS, POLICE SPENT NEARLY 10 YEARS WORKING ON THE HIGHLY-SOPHISTICATED PATROL SIMULATION MODEL. THE MULTITUDE OF PROBLEMS ENCOUNTERED DURING THIS PERIOD ARE EXAMINED IN DETAIL. A NEW POLICE ADMINISTRATION ASSUMED COMMAND IN 1973 AND DECIDED TO ABANDON THE ORIGINAL CONCEPT IN FAVOR OF A TOTALLY NEW APPROACH TO POLICE PATROL. A CONSULTANT WAS CALLED IN TO DOCUMENT THE ASSIGNMENTS OF THE SWORN PATROL OFFICERS, TO RECOMMEND A REORGANIZATION OF THOSE ASSIGNMENTS TO PROVIDE MORE OFFICERS FOR STREET PATROL, AND TO DEVELOP NEW SECTOR BOUNDARIES. AFTER IMPLEMENTATION OF THE NEW PROGRAM, 'ZERO CAR AVAILABILITY' WAS REDUCED FROM 26 PERCENT OF CALLS TO 5.9 PERCENT. HOWEVER, A GREAT DEAL OF THIS WAS DUE TO A LARGE SHIPMENT OF NEW POLICE CARS AND IMPROVED MAINTENANCE TECHNIQUES WHICH REDUCED DOWNTIME FOR EACH CAR. THE CASE STUDY EMPHASIZES THE DIFFICULTY OF GETTING TRADITIONAL LAW ENFORCEMENT OFFICERS TO UNDERSTAND THE USE OF COMPLEX TECHNOLOGY AND THE DIFFICULTY OF GETTING COMPUTER SOFTWARE VENDORS TO UNDERSTAND THE PERSONNEL COMPLEXITIES OF A POLICE DEPARTMENT. IT ALSO EMPHASIZES THE PROBLEMS ENCOUNTERED WHEN ADMINISTRATORS CHANGE AND ADVOCATES FOR A PROGRAM VANISH. GREATER INTERACTION BETWEEN MODEL BUILDERS AND MODEL USERS IS URGED. REFERENCES AND NOTES ARE APPENDED. (GLR)