Alastair Carmichael, 49, of Perrays Crescent, Dumbarton, was last seen by his family at his home address around 10pm on Friday.
Alastair is white, 5ft 8 inches in height and of stocky build with grey receding hair. He also wears glasses. When he was last seen he was wearing blue jeans, a light blue polo top, black lightweight jacket and Voi trainers.
Inspector Claire Miller at Dumbarton Police Office said today: "Alastair has recently being going through some personal issues and has never been missing before.
"He did not turn up for his work this morning which is completely out of character.
"He does not have his mobile phone or any money with him and his family and police are becoming increasingly concerned for his safety.
"Extensive enquires are ongoing in the Dunbartonshire area to trace Alastair, and officers are currently studying CCTV in an effort to gather any more information that may assist this investigation.
"I would urge anyone with any information on Alastair's whereabouts, or who may recognise his description to come forward to police as a matter of urgency."
Anyone with information should contact Police Scotland on 101.