One of the ways to be proactive about safety is by staying informed of who is living and working in your neighborhood. A sex offender registry is a list of all convicted sex offenders in a state. Sex offender registries generally include the offender's address, physical appearance, and criminal history. All fifty states require individuals convicted of certain sex crimes to register. Those convicted of more violent crimes are typically required to remain registered for a longer period and to update their address more frequently.