Harrison joins BBC Studios on a nine-month attachment as senior VP of commissioning and content for global services. He will report into Paul Dempsey’s global distribution division.
BBC Two controller Patrick Holland will cover BBC Four during Harrison’s absence.
Harrison will work on the creation and distribution of original programming for digital services that BBC Studios owns and operates around the world.
BBC Studios runs a number of linear and digital services around the world including BBC Earth, BBC Brit and BBC First and a digital service, BBC Player, in Singapore and Malaysia.
At factual channel BBC Four, Harrison has backed programming ranging from the Slow TV initiative to “The Secret Life of Landfill” and “British History’s Biggest Fibs” to the acclaimed “Bros: After the Screaming Stops” and “Life Drawing Live.”
Tim Davie, CEO of BBC Studios, said: “Cassian’s extensive experience and excellent track record in creating and commissioning great British television will help supercharge our offering to international viewers as we look to take the premium, original content for which the BBC is world renowned, to an even wider global audience.”
Charlotte Moore, Director, BBC Content added: “Under his leadership, BBC Four has flourished and achieved continued success. His broad range of interests and eclectic taste make him perfectly placed to take on this new global role and I would like to wish him all the best.”
Before BBC Four, Harrison spent five years as commissioning editor for science, natural history and history across BBC One, Two and Four.