BOLO stands for "Be On the Lookout" and is an acronym used in law enforcement to instruct officers or the general public to watch out for a suspect or a criminal. It is a broadcast issued from law enforcement agencies to alert officers in other parts of a city or country to be on the lookout for a fugitive, criminal, or law offender that is on the run. A BOLO alert can be broadcast to local law enforcement agencies to alert them to a missing child, and a teletype can be sent locally or regionally.

When a BOLO is issued, it relies on the efforts of the public to help find the suspect or criminal. The public can report any sightings or information to the nearest police station or through the Crimestoppers program, which is anonymous and does not ask for the callers identity. BOLO alerts have been successful in helping law enforcement agents make arrests and avoid making wrong arrests.