Iain Wilton joins from lobbying consultancy Quintus where he has been an associate director since last January.
Prior to this he spent six years as head of communications and public affairs at Marylebone Cricket Club (MCC).
In the 1990s, he spent five months working a special adviser to ex-Tory leader Michael Howard, during his time as employment secretary. He also spent 18 months as an aide to the former health secretary William Waldegrave.
Wilton joins as head of media and campaigns, initially on a 12-month contract. He jointly replaces programme director for communications Ed Welsh and programme director for public affairs Alan Wardle, both of whom left in the summer.