Police are appealing for public assistance to help locate missing 18-year-old Christian Stevens.
Christian was last seen in Blaxland, New South Wales on 1 December, however investigators believe he has returned to Victoria.
Police and family have concerns for his welfare due to his age and he has a medical condition.
Investigators have released an image of Christian in the hope someone recognises him.
Anyone who sights Christian or has information on his whereabouts is asked to contact Glen Waverley Police Station on 9566 1555.