Chapter 3 analyzes the demographic makeup and composition of state sex offender registries. The data reject the popular narratives of incomplete registries filled with dangerous individuals. The chapter begins by investigating the widely reported counts of registered individuals from the National Center for Missing and Exploited Children (NCMEC). While NCMEC reports that there are nearly one million registrants nationwide, no true national registry exists to confirm this claim. Further, independent studies indicate that many registrants simply do not live in their listed community – they may be incarcerated, committed, deported, or deceased. Additionally, the data refute common arguments that registries are systematically incomplete with regard to “missing” registrants. The chapter next examines how registries reflect broader racial dynamics. The typical registrant is middle-aged and white. However, registries are disproportionately black, and black registrants are overclassified with respect to recidivism risk. Finally, the chapter dissects the technical and data challenges affecting registries. While intra-registry duplicates plague few jurisdictions, many registries contain individuals present on other states’ registries. This chapter contends that policymakers should account for these deficiencies when considering sex offender policy.