Exedra is designed to help brand owners recognise and maximise the revenue potential of their brands.
Cagney's existing brand consultancy BrandAid will become a division of Exedra, providing quantitative support for creative development projects.
Exedra will be jointly run by Ben Kingsmill, who joins from McCann Erickson to launch the venture, and Murray Chick, currently chairman of Chick Smith Trott.
Exedra's services have already been retained by Independent News & Media, First Choice Holidays and the Silver Spoon Company.
Exedra translates from the Greek as "a chamber designed for debate and discussion" and it will work with a network of external consultants together with consultancy staff.
Chick said: "We have decided it is the right time to expand our business base. Exedra will be differentiated in the marketplace by our ability to embrace the highest level creative thinking into our strategic analysis and solutions."
Kingsmill said: "It is our creative attitude that sets us apart, we believe in the power of branded ideas and the intelligent use of research. We are unrestrained by media choice and do not base brand advice on unsubstantiated opinion."