Accreditation, long used to signal quality among hospitals and universities, has been available to police, fire, and public works departments since the late 1980s. For public service departments, accreditation is a voluntary process that demands significant organizational resources without a guaranteed outcome. Why would city officials devote scarce resources to such an endeavor? Two explanations are examined. First, accreditation may be a rational response to a history of trouble or the potential for future crisis. Second, municipalities may use accreditation to build a reputation for professional administration of public services. The authors use Poisson regression to test these explanations on a new data set of midsize cities.