The Annual Report to the Nation on the Status of Cancer that was released today shows continued declines in both the rate of new cancer cases and the rate of cancer deaths in the United States over the past several years. The incidence data used in the report were gathered from population-based cancer registries that participate in the NCI’s Surveillance, Epidemiology and End Results (SEER) program, and/or the CDC’s National Program of Cancer Registries (NPCR). Information on mortality rates comes from CDC’s National Center for Health Statistics (NCHS). This article explores the role of population-based cancer registries.