The move is designed to boost corporate and Government funding for the organisation's 7,000 youth groups.
Gillan Media, which has been appointed following a five-way pitch, will also help the charity to find a high-profile patron for the charity. The previous patron was the Queen Mother.
Gillan Media MD Adrian Gillan said his first task was to develop a comms strategy aimed at boosting national media coverage and targeting Government and businesses.
This will include a bid to raise the profile of CEO John Bateman 'as a prominent spokesman on issues affecting young people,' according to Gillan.
Gillan will also be providing media training and assisting regional PR efforts. The charity has 41 regional groups, 40,000 youth workers and provides services to around 750,000 young people.