Her first task will be to devise a communications plan around the charity's tenth anniversary next year.
TreeHouse was set up in 1997 by a group of parents with autistic children. It currently provides education for 49 pupils aged three to 13 in a specialist school in Muswell Hill, north London, where it pilots innovative teaching techniques.
Coveney will be responsible for planning campaigns aimed at raising autism on the political agenda. The charity has ambitions to set up a national training centre to help others found similar schools around the country and provide information and support for parents.
Coveney, who has worked as a senior media officer at The Children's Society for four-and-a-half years, joins TreeHouse on 2 October.
Previously she was a journalist, working for newspapers, BBC radio and ITV.
Coveney worked on The Children's Society's national Safe & Sound campaign to ensure runaway children have a place to stay. It got free coverage and advertising from Premier Media Group, the broadcaster of Premier Christian Radio (PRWeek, 4 June 2005).
