Phillips' direct marketing career includes stints at WWAV Rapp Collins and Joshua, where she was chief operating officer and led accounts including Royal Mail, Renault and British Airways.
She left Joshua to launch McCann Relationship Marketing, joining as managing director, and has worked on accounts including L'Oreal and Norwich Union. She left MRM to take a short career break to start a family before accepting the role at Proximity.
At Proximity, Phillips' brief will be to lead the business development team and to drive the agency's new business.
Phillips joins Proximity in January and her appointment follows that of Heresy partner Tim Patten as managing partner, which was announced earlier this month.
Former Lowe chief executive Thomas took over at the agency earlier this year, after it was revealed that Simon Hall, co-founder of the agency, would be leaving at the end of the year with no job to go to.
Hall followed co-founder and creative director Chris Barraclough out the door. Barraclough left earlier in the year to launch a start-up, triggering a shake-up at the agency.
Proximity London is also strengthening its creative team with the appointment of Debi Bester and Sonia Sigleton from Harrison Troughton Wunderman.
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