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You don’t have to wait a mandatory amount of time to file a missing person report. The faster you notify the police that your loved one is missing, the faster they can begin searching. Go to your local police department to file a report. You should understand the limits of what the police can do, especially if the missing person is an adult. It is not illegal for a person to go missing. To complete the missing persons report, you'll need to provide detailed information about the missing person's physical characteristics and last known location. Have the following information ready when you go to the police station to file the report:  Three current photos of the person A list of nicknames or aliases used by the person A physical description, including height, weight, age, hair color, eye color, build, etc. A description of the clothing and shoes the person was last seen wearing A list of possessions the person might be carrying, such as jewelry, glasses, contact lenses, accessories, a purse, a wallet, ID cards, etc. A list of scars, tattoos, and other identifying characteristics A list of medications the person was taking, as well as allergies, handicaps, and other medical conditions A list of relatives or friends of the missing person, along with contact information A list of places the person frequents A description of the person’s car or a different mode of transportation (a bicycle, for example) if applicable A description of the situation surrounding the person's disappearance Make sure you obtain a case number for your missing person's report. Write down the name of the person in charge of your case. Contact this person when you wish to follow up. The US Department of Justice operates this system. NamUs lets you upload information about a missing person for use by law enforcement officials, agencies, and individuals. The site helps missing persons cases wrap up sooner by providing this information to the public. You can use other databases designed to help find missing persons, many of which are geared toward specific characteristics. Consider registering with additional databases to gain access to their free services and resources to help you find your missing person.  The National Center for Missing and Exploited Children specializes in providing services for families of children who are missing. After you have reported a missing child to law enforcement, you can call the National Center for Missing & Exploited Children at 1-800-THE-LOST(1-800-843-5678). The National Alliance on Mental Illness provides resources for families of people with mental illness who have gone missing. Their website contains potentially useful materials, including suggested guidelines and forums.

Summary:
Contact the police as soon as you have reason to worry. Provide the police with information about the missing person. Keep a record of the report. Contact the National Missing and Unidentified Persons System (NamUs). Register with other missing persons databases or review their resources.