South Wales Police is trying to trace a 33-year-old man after he went missing from Cardiff centre on Saturday 26th of August.
Police say Richard Maddern-Hazell has a history of mental illness and they're concerned for his welfare.
He's described as being a white man, around 5ft 11ins tall and of slight build.
He was last seen wearing black trainers, navy jeans, a green jumper and a black and grey jacket.
Police have asked anyone who does see him to get in touch but have warned the public not to approach him.