Reporting to general manager Ruth Warder, Mitchell (pictured) will oversee the division, whose clients include Heineken, Asics, Paypal and WW.
Mitchell will join from Brooklyn Brothers, where she has been managing partner, working with brands including L’Oreal, Mini and Jaguar Land Rover. She was previously creative director at The Engine Group, and has worked at Mischief, Slice, Frank and Shine.
Warder said: "Miranda combines immense earned, integrated and creative pedigree – exactly what we need for this critical leadership role. It’s exciting to bring Miranda and her experience into our team at a time of clear evolution. Miranda has fantastic energy, is great fun, and I know that the team and clients are going to love working with her."
Mitchell said: "Edelman’s incredible reputation goes without saying and the genuine appetite for innovation happening in the business makes it such an exciting time to join. I can't wait to get stuck in with the team."
She is due to join Edelman in April.