The appeal comes as concerns grow for the safety of 15-year-old Mia Hassell, who has not been seen or heard from since lunchtime yesterday.
The last confirmed sighting of the youngster was at around 12.45pm on Friday, when she was seen walking near to the popular Wallace Park in Glenfarg, Perthshire.
The teenager is described as being 5ft 3in tall, of slim build, with long brown hair.
She was dressed in a black shirt dress and white-coloured Nike training shoes when she disappeared.
Officers are calling for members of the public to get in touch if they have seen Ms Hassell or can pass on any information that would help track her down.
Anyone who may have seen her or knows her whereabouts is being asked to get in touch with Police Scotland on the 101 helpline, quoting incident number 1780.