Omnicom has merged two of its media agencies — Mediahub and Hearts & Science—to create a new entity called Hearts United. 

It will be led in the U.S. by Nicole Estebanell, who previously served as CEO of Mediahub U.S. The company has not yet disclosed a global CEO for the new entity. 

Estebanell’s senior team includes a mix of Mediahub and Hearts & Science executives. They include former Hearts & Science executives Lauren Amster (Client Operations), Nadalie Dias (Transformation), Jemma Jang (Client Success), Sam McKnight (Finance), Kaila Roti (Content), and Georgina Thomson (Investment); and Mediahub’ s Janet Levine (Strategy), Wendi Dunlap (Analytics), Shea Kelly (Client Success),) and Drew Watson (Planning).  

Hearts & Science’s most recent US CEO was Chris Stanger, who left earlier to join agency client AT&T. In the interim Omnicom Media North America CEO Ralph Pardo had been overseeing the US operation.    

The new agency network operates across 40 markets with an estimated $9.1 billion in 2025 billings, according to the agency. Between 2021 and 2025, Hearts & Science increased its billings by 50%, while Mediahub grew 33% and Omnicom says that new business momentum has carried into 2026.  

Omnicom Media CEO Florian Adamski. Stated, “In bringing them together as Hearts United, we have created a new globally scaled network built from complementary strengths, approaches and footprints, and grounded in the shared principle of putting client growth at the heart of every decision.”