Studzinski will join Karmarama in August and be an equity partner. He replaces Dave Buonaguidi, a co-founder who left in July 2014.
Caitlin Ryan, the group executive creative director, and Sam Walker and Joe DeSouza, who will continue as joint executive creative directors, will report to the agency's board.
Jon Wilkins, the executive chairman at Karmarama, said: "Nik is one of the most progressive leaders in the creative world and a respected craftsman. He’s also a genuinely great guy and will help us bring more creative firepower across the entire breadth of our offer."
Studzinski was the executive creative director at Droga5’s London office, which he helped launch in 2013 alongside Kevin Dundas, the chief executive, who has also since left the agency.
Studzinski said: "I’ve enjoyed an incredible journey with Droga5 and it took something exceptional to make me even think about leaving.
"Karmarama is a dynamic independent agency with a unique spirit, incredible talent across all the disciplines, and a great offering. I love its ambition to become the most progressive creative agency."
David Droga, the Droga5 founder, told Campaign that Studzinski’s departure was entirely amicable, adding that the agency is planning to appoint a new chief executive and a new chief creative officer later in the summer.
Duncan Marshall, a partner and executive creative director at Droga5, will relocate to London to replace Studzinski on an interim basis.