BroadView will now operate within 4Media under a new name The StoryBuild Agency, with Maister named as MD of the new unit.
The acquisition follows 4Media’s move last month to 6,100 square-foot headquarters in Clerkenwell, which features a new TV studio and two new radio studios.
Maister, the former national TV and radio reporter who founded TV consultancy The London Bureau in the 1990s, said: "This move means we can offer our clients a much broader range of services with much greater firepower. In addition, I plan to help the 4Media Group rapidly develop its video proposition across earned, owned and paid-for channels."
4Media CEO Edward Cyster said: "Stuart will help us put great storytelling at the heart of our service, develop bigger strategies for our clients and up our game in the way we develop, produce and leverage video content."
After selling The London Bureau to Medialink, Maister formed BroadView in 2001 as a video storytelling specialist for brands.
Maister retains a minority stake in BroadView following the 4Media acquisition. The sale price has not been disclosed.