The assignment comes after Emap Performance handed its planning account to Naked from the PHD sister agency Rocket earlier this year.
Starcom Motive and Naked will be responsible for developing advertising campaigns for its brands including Sneak, Big City, Magic and Kiss and its Smash Hits!, Q and Mojo TV channels.
The advertiser spends the bulk of its advertising spend on support for its radio channels and magazines.
In April, Mother unveiled a launch campaign for Emap Performance's new teenage celebrity magazine Sneak, having won the account the previous month.
Rocket, and before that PHD, had handled this account for more than 11 years. It has been retained on the Emap Performance roster in a capacity to provide strategic advice. The loss of Emap Performance led to the departure of Rocket's media director, Jean Ash, who was responsible for the account.
No-one at Starcom Motive was available for comment as Campaign went to press.