Jones was previously the managing director of digital agency Realtime before it merged with EHS and Brann in 2000, when he became vice chairman of EHS Brann.
"After 13 years steering Realtime from 10 staff to several hundred, I need to work with like-minded people. The partners at Mook remind me a lot of the original team I joined at Realtime and, since starting this July, I have a good feeling about helping them expand their business and have some fun along the way," Jones said.
The appointment follows Mook's recent appointment by the V&A to create the website for its autumn exhibition 'Encounters: The Meeting of Asia and Europe' after a successful collaboration on the Vivienne Westwood site earlier this year.
Tom Adams, communications director of Mook, said: "As we approach the end of our fifth year, we're keen to continue growing, and realise our creative and commercial ambitions for the agency. Phil brings just the right combination of expertise, energy and perspective we need to make that possible."
Mook specialises in the youth, media and music markets and includes the BBC, EMI Music and MTV Networks Europe among its staff. It has 12 permanent staff and was formed in December 1999.
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