Searching for Scotland's missing people
More than 730 people in Scotland have been are regarded as "long-term" missing, according to figures seen by the BBC.
A new report also shows that almost 22,000 missing person investigations were made in Scotland last year, 62% of them involving children.
About 99% of them have since been found safe and well including all children who went missing.
Police Scotland's new national missing person unit has been analysing missing person data with the police database going back to 1957.
BBC Scotland correspondent Lucy Adams reports.