This article reviews studies of dental practice and essays on practice management that have included information on the economic contributions of oral hygiene services. Several studies found that these services were less remunerative than other services and recommended that dentists delegate these functions when possible. However, one study noted that performance time, as well as delegation, influenced practice productivity and also reflected the practice's concept of care. Some practice management authors indicated that poorly managed practices without an excess of patients do not benefit economically from hiring a hygienist; but for practices with good management capabilities and an excess of patients, a hygienist may be able to make a major contribution to practice productivity. The lower remuneration for hygiene services and the high percentage of practice time required to provide a complete prophylaxis once or twice a year to each patient led several authors to doubt that dentists would or could provide these services themselves. The data in the reported studies, however, are insufficient to support firm conclusions about the profitability of hygienists' activities in dental practice.