Elliott joins Ptarmigan following a period consulting following the buy-out of her 45-strong agency Keene Communications in 2006.
She replaces Ptarmigan's former MD Jason Madeley who has taken a career break to go traveling. Madeley had been at the agency for 13 years.
Elliott is charged with developing existing plans of opening an office in London.
Associate director Helen Wills has also been made a board member at the agency with responsibility for Ptarmigan's work in the public sector.