Rainer, previously client services director, has been with Archant for six years. Before that he worked at Saatchi & Saatchi, working on clients including the AA, Pentax and Uniroyal Tyres.
In his new role, Rainer will report to Ian Davies, director of development.
Archant chief executive John Fry said: "The success of Dialogue is dependent on gaining and retaining new clients. Chris Rainer has been responsible for this area and will continue to take responsibility for growth as we develop into new client areas."
The division, based in Norwich, produces magazines for Saab GB and the Association of Teachers & Lecturers, as well as Live Well for the GNC.
Archant is best known for publishing the Ham&High, the local newspaper for the Hampstead and Highgate areas in London.
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