Bemfica will work closely with Linus Karlsson, chairman and chief creative officer of McCann Erickson in London and New York, and Matias Palm-Jensen, chief innovation officer for McCann Erickson in Europe.
McCann, which holds the global accounts for Nestlé brands including Nescafé and Nesquik, has previously managed creative on a market-by-market basis.
Bemfica was born and raised in Brazil and has worked for JWT Madrid since 2008.
His previous agencies include Propeg, Colucci and Almap BBDO in Sao Paulo, and also as a creative director at DM9 DDB, where he honed his digital and integrated skills. He also founded Escola Cuca, an advertising school in Brazil.
Clients he has worked on include Audi, Volkswagen, Honda, Corona, Johnson & Johnson, Kraft, Whirlpool, and Unicef.
Karlsson said: "Miguel has not only a proven track record in doing great work on big global brands, but he is also one of the most passionate and nicest people in the business. He will play an important role in the re-invention of McCann."