Mr Cook hasn't made contact with his family in four weeks.
Mandurah Detectives are seeking information regarding the whereabouts of 46 year old Adam Heath Cook.
He last made contact with family about four weeks ago.
He's described as fair skinned, approximately 186 centimetres tall, with a slim build, short brown hair and blue eyes.
It is not known what he was wearing.
Concerns are held for Adam’s welfare, and anyone who sees him or has information regarding his whereabouts is asked to call police immediately on 131 444 or contact Crime Stoppers on 1800 333.