In his new post, McGrath will develop broader strategic thinking across the agency's client base.
McGrath's appointment marks Karmarama's move towards reshaping its management line-up after the departure of some key figures.
Karmarama's previous planning partner, Nick Barham, left the agency last July for TBWA\China as its national planning director. In November 2005, Naresh Ramchandani quit the agency, which he co-founded with Dave Buonaguidi six years ago. His departure left Buonaguidi as the sole creative partner.
Earlier in 2005, the agency also lost its creative team of Vic Polkinghorne and Matt Janes to Saatchi & Saatchi and last month, Paddy Barnes, the agency's joint managing partner, left the agency to set up a popcorn-making business.
McGrath's appointment follows his resignation from United, formerly HHCL United - the agency he joined in 1998 as a planner. He was previously a brand manager at Procter & Gamble.