A hospital registry is a collection of prospectively recorded information about patients who have a specific condition or who received a specific type of treatment. Hospital registries are beneficial for the patient, physicians, and administrators and serve several purposes, with the primary purpose being quality control. This article focuses on the role of registries at the hospital level and their advantages compared with other data sets. We also discuss how to implement a hospital registry and how to ascertain registry quality. Finally, we describe the problems inherent in any hospital-based registry and the ways in which the data collected in a registry can be appropriately analyzed.