Mariana O’Kelly is EVP/Executive Creative Director at Leo Chicago, where she leads creative for the entire Kellogg’s portfolio. With over two decades of global experience, she’s known for crafting emotionally resonant, culturally sharp work that drives impact.

Previously Global ECD at Ogilvy, Mariana has won multiple Cannes Lions Grand Prix—including three in Audio—and more than 70 international awards. She served as Cannes Lions Jury President, was named one of Adweek’s Creative 100, and recognized by the Gunn Report as one of the top creative leaders in the world.

Originally from South Africa, Mariana is also a passionate advocate for diversity in the industry, having led gender transformation efforts across agencies. She brings a human-first leadership style and a belief that great ideas should feel like authentic conversations.

If she wasn't in advertising, she would renovate old houses or teach art to kids.