The Maricopa County Sheriffs Office is responsible for vitally important law-enforcement functions in one of the largest counties in the nation. It defines its core missions as law-enforcement services, support services, and detention.MCSO falls seriously short of fulfilling its mission in all three areas. Although MCSO is adept at self-promotion and is an unquestionably tough law-enforcement agency, under its watch violent crime rates recently have soared, both in absolute terms and relative to other jurisdictions. It has diverted resources away from basic law-enforcement functions to highly publicized immigration sweeps, which are ineffective in policing illegal immigration and in reducing crime generally, and to extensive trips by MCSO officials to Honduras for purposes that are nebulous at best. Profligate spending on those diversions helped produce a financial crisis in late 2007 that forced MCSO to curtail or reduce important law-enforcement functions.In terms of support services, MCSO has allowed a huge backlog of outstanding warrants to accumulate, and has seriously disadvantaged local police departments by closing satellite booking facilities. MCSOs detention facilities are subject to costly lawsuits for excessive use of force and inadequate medical services. Compounding the substantive problems are chronically poor record-keeping and reporting of statistics, coupled with resistance to public disclosure.Our focus in this paper is exclusively on effective law-enforcement. We find that MCSOs effectiveness has been compromised for the past several years by misplaced priorities that have diverted it from its mission. We recommend several reforms that will increase the effectiveness of MCSO specifically as well as law-enforcement agencies throughout Arizona.