Powell, who turns 60 next week, is due to step down as chairman of BMP DDB some time later this year, but will take a non-executive role at the agency and will take up the job at the National Endowment for Science, Technology and the Arts on October 31.
His decision to leave the role he took up five years ago was not related to the Nesta move, but because he said it was "ridiculous" to chair an advertising agency after the age of 60.
He will assume the role of chair of Nesta on October 31, taking over from Lord Puttnam, the producer of 'Chariots of Fire'.
BMP DDB is reported to be undertaking a radical restructure of senior management. One of the most respected figures in the advertising industry and widely praised for his intelligence, Powell has worked at BMP DDB for 34 years, joining six months after it was formed in 1969.
He stepped down from the chief executive role five years ago to take the part-time position of chairman, and has been expanding his outside interests since, with roles as the chair of Think Tank, an advisory group to the British Council, and on the boards of United Business Media and Riverside Studios. Powell was formerly chair of the Ealing, Hammersmith & Hounslow Health Authority.
Powell said: "It will be a challenge to follow the chairmanship of Lord Puttnam, who has been the inspiration for Nesta and led it through its formative years. Nurturing innovative talent to good purpose enriches us all. I'm excited to be asked to be part of such an important and interesting mission."
Nesta was established in 1998 with an endowment from the National Lottery to promote talent, innovation and creativity in the arts, science and technology. Powell takes the role of chair for four years to be paid 拢23,850 a year.
Making the appointment, culture secretary Tessa Jowell said: "I am delighted that Chris Powell has agreed to take on this key role at Nesta. His advertising background will be invaluable in helping promote Nesta's ideas and strategies and I know he will provide the vision and leadership necessary to drive forward these important agendas."
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