The role became free after previous managing director Stephen Priestnall left for personal reasons. Phillips was formerly business group director at Syzygy before leaving for MRM in October last year. He will take up the Syzygy role in July.
Pipa Unsworth has been promoted to deputy managing director and will manage Syzygy alongside CEO Marco Seiler and chief technology officer Frank Wolfram, until Phillips arrives. Unsworth was previously insight director.
Phillips' career has spanned interactive communications, advertising, direct marketing and brand development, through roles at Collett Dickenson Pearce, DDB London, Ogilvy & Mather and MRM Partners.
Seiler said: "In Gareth's time as business group director at Syzygy, he steered the agency to gain sustained growth from its existing client base. His appointment as managing director is the turnkey ingredient, which will move Syzygy on to the next level of growth."
Syzygy specialises in eCRM systems, e-marketing and designing websites.
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