Police are urging drivers in the Jandakot area to keep a look out for a missing 40-year-old man.
Adam Tyler was last seen around 10.30pm on Tuesday, January 4.
He may have trouble communicating with others and may run off if approached.
Mr Tyler is described as fair skinned, 180cm tall, of solid build with short brown hair.
He is believed to be wearing blue and white pyjamas and shorts.
Motorists in the Jandakot area are advised to drive with caution and keep alert for any signs of Mr Tyler near local roads, as he may approach moving vehicles.
Anyone who sees Mr Tyler is asked to report any sightings to police on 131 444 and monitor his location until officers arrive.