Beattie, a former producer at GMTV, is to join at the start of 2007.
C&W CEO Jonathan Shore said Beattie's work developing Pleon's European offering meant he was ideal to develop C&W and WPP sister firm GCI's presence across the Continent.
Beattie will slot in between C&W deputy MD Caroline Page (on maternity leave) and Shore, who was MD until being promoted to CEO a year ago.
C&W has also recruited broadband firm Bulldog's head of corporate comms Gladys Elia. She joins on 8 November in the business and tech MD role vacated by Susanna Davidson (PRWeek, 21 July).
The agency has promoted corporate MD Stephen Doherty to a new role of director of operations. He will continue to oversee the corporate team, but day-to-day management will be shared with corporate affairs director Lee Murgatroyd.
Beattie's role at Pleon is to be assumed by Jennifer Helfer. The US-born UK MD joined Pleon from Firefly Communications in 2004.