Caseley will join the arts funding body later next month in the newly created role of executive director of external relations.
The role has been created following a reorganisation of the body that has seen the communications directorate boosted to a team of 46, with added responsibility for policy and research, as well as internal communications.
The other areas under Caseley's responsibility are press and PR, public affairs, marketing and events as well as information and library staff.
Caseley said one of his priorities will be to create stronger links with the Department for Education and Skills. This is part of Arts Council England's attempt to become more involved with social inclusion issues.
He explained: 'A lot of our work and the projects funded have the aim of getting people more involved with their communities through the arts.
The aim is to make the arts part of the fabric of every day life.'
Caseley reports to CEO Peter Hewitt. Wendy Andrews, the body's previous most senior PRO whose executive director of communications role has been made redundant, is understood to be returning to freelance work.
Arts Council England, previously called The Arts Council of England, gained £2bn of funds in this year's public spending review to invest in the arts from now until 2006.
Meanwhile at Ealing, deputy communications department head Candy Stern will become acting head of department. She will be assisted by consultant Chris Myers, who becomes acting head of PR.
One of Stern and Myers's priorities will be to continue developing the communications side of a project launched this year to make the council more customer focused. It is not yet known whether the council will look for a direct replacement for Caseley.