Claudia Lawrence's mother 'she could be out there'
7 June 2013 Last updated at 13:57 BST
Claudia Lawrence vanished without trace in March 2009 at the age of 35 after failing to turn up to work as a chef at York University.
Police launched a murder inquiry but a body has never been found. At it's peak 100 police officers were dedicated to the inquiry and the cost of the police operation so far stands at over three quarters of a million pounds.
Claudia's mother, Joan Lawrence, has never given up hope that her daughter is alive and told BBC Radio 5 live's Victoria Derbyshire that "she could be out there somewhere".