The move follows the flotation of the group, which owns the HMV music and Waterstone's bookstore brands, four months ago.
The newly created in-house function will be headed by Paul Barker, currently Freeserve's director of corporate affairs, with responsibility for its investor relations and financial communications.
Barker, a former corporate comms chief for Leicester City Football Club, will join at the start of 2003 reporting directly to CEO Alan Giles.
There are no plans to recruit further in-house corporate comms roles and Barker will be assisted by Brunswick, which was hired as the group's retained corporate and financial agency two weeks ago, following what is understood to have been a five-way pitch.
This boost in corporate communications comes as the firm attempts to drive through a programme of growth, including refurbishment of its Waterstone's stores, adding new HMV stores and driving sales in the DVD and computer and console games areas.
Giles said: 'This really is a new era for the company.'
Consumer PR for the Waterstone's and HMV brands is handled by in-house teams which are unaffected by the creation of the corporate function.
At HMV, PR is led by head of press and PR Gennaro Castaldo.
The Brunswick team is led by partner Susan Gilchrist as well as senior associate partner Charlotte Elston.
Financial PR during the firm's float in May was handled by Finsbury, which also handled corporate PR for the pre-merger company HMV Media.
A Brunswick spokeswoman added that the corporate communications boost was vital to better communicate with new, post-merger audiences including shareholders and analysts.
The group had sales of £1,655m during 2001/2002 and has around 13,000 employees.
Barker joined Freeserve from Leicester two years ago. He reports to general counsel David Melville and acting CEO Eric Abensur.
A spokeswoman for Freeserve, which was acquired by French ISP Wanadoo in February 2001, said: 'No decision on a successor has been made and the company is considering all the options at this stage.'
Barker has worked in journalism and was publisher and editor-in-chief of Financial Times Media.