Phillipson was previously managing director at the marketing agency Propaganda, where he worked with Habitat as their interim marketing director.
He has also held senior marketing director roles at First Direct and internet bank Smile, following agency roles at Saatchi & Saatchi and JWT.
Phillipson said he was joining Altitude as it "goes from being not just a leading UK venue brand, but a global venue brand".
Altitude London has three venues -- Altitude 360, The River Room and The Millbank Cinema and Media Centre, the last being opened in 2007 by Conservative Party leader David Cameron.
The Altitude 360 venue has been used by a variety of high-profile names since 2007, including the US presidential candidate John McCain, as well as Kate Moss and Girls Aloud.
Meanwhile, the Millbank Cinema and Media Centre is currently being used by the Conservative Party in the lead-up to next month's General Election.