'Trevor's disappearance was always the most baffling'
In September 1998, I was appointed national coordinator for Operation Trace, a specialist gardai unit set up to investigate the disappearance of six women.
All had disappeared in a three-year period in an area of the country that came to be known as the Vanishing Triangle.
A number of other cases - both historical and current - were revisited as part of the investigation, including the disappearance of Trevor Deely, which was always considered to be one of the most baffling.
Unlike some of our cases, Trevor had not gone missing while walking on a remote country road in the dark of night or had not been seen for a number of days.
Quite the contrary. His movements can be viewed on CCTV footage obtained from business premises in the Baggot Street area of Dublin. He can clearly be seen walking in the direction of Haddington Road.
Despite intensive gardai investigations, no trace of Trevor was ever found after that.
All the normal inquiries undertaken when a person is reported missing - checks on bank and savings accounts, airports and ferry ports, hospitals and clinics - drew a blank.
His personal life was examined to see if anything might have caused him to leave home and not have any contact with his loved ones.
This could be personal difficulties, volatile relationships and work-related issues. In his case, nothing was identified. This would tend to suggest that his leaving was not voluntary.
Trevor's case sparked huge media interest. Here was a young man enjoying a quiet Christmas night out with work colleagues, who turned from one main road into another and was never seen again.
This year marks the 15th anniversary of his disappearance. In the intervening years, his family have continued with their campaign to ensure that the search for Trevor continues.
I pray there will be a successful outcome to the current search.
Alan Bailey is a former detective sergeant with the Garda Serious Crime Review Team