Gardaí have issued a renewed appeal for information on the disappearance of Trevor Deely.
The 22-year-old went missing from Dublin city centre on December 7th 2000.
He attended his work Christmas party at the Hilton Hotel in Dublin 2 and went on to the now-closed Buck Whaley's nightclub on Leeson Street.
He left the club between 2:30am and 3:25am the morning of December 8th that year.
The weather on the night was extremely wet and there was a taxi strike in progress.
At 3.35am, Trevor called to his place of work at Bank of Ireland on Fitzwilliam Place.
CCTV footage of the rear entrance of the premises at 3:35am shows an unknown man talking with Trevor at the back gate.
This man has never been identified.
Trevor was last seen on CCTV passing the since-removed Bank of Ireland ATM on Haddington Road at 4.14am.
Around 30 seconds later, a man was captured on CCTV walking in the same direction as Trevor.
Trevor Deely is described as 6'1", of slim build, with short red/brown hair and of fair complexion.
When last sighted he was wearing a mustard and brown checked shirt, beige/grey corduroy flared trousers, dark deck shoes with white stripes and a green padded jacket.
He was carrying a large, dark blue umbrella with white 'ACC Bank' lettering.
Gardaí at Pearse Street Garda station are appealing for any information that could assist the investigation into the disappearance of MrDeely.
They say even the smallest piece of information, which may seem insignificant, may assist the investigation.
Anyone with information is asked to contact Pearse Street Garda station on 01-666-9000, the Garda Confidential Line at 1800-666-111 or Crimestoppers on 1800-250-025.