Megan's law requires all states to develop measures to notify the public of the whereabouts of all sex offenders in the community. Authorities have published websites with databases that contain the names and addresses of all sex offenders in a state. Some websites have a mapping function showing the locations. The offenders are sometimes required to report to local police officers and to inform their neighbors of their status--different states have different procedures for registering. Some states won't provide information on sex offenders currently serving time at a correctional facility.