Sharon Callahan

CEO, TBWA\Worldhealth & Chief Client Officer, Omnicom Health

Sharon Callahan serves as Chief Client Officer of Omnicom Health Group, helping clients access Omnicom’s deep healthcare talent and developing engaging innovative approaches for teamwork to maximize results for global brands. In addition, Sharon is also CEO of TBWA\WorldHealth, a global agency network that she re-founded in 2017.


Sharon’s 30+ years of healthcare marketing is a synthesis of strategic skills developed in consumer and professional advertising, medical education, clinical programs, publishing, and digital. Consistently helping clients to leverage their value through the seamless integration of multiple communication channels, Sharon’s boundless energy is credited with promoting excellent communications and maximized sales.


Innovative and entrepreneurial, Sharon built her career at Omnicom as Executive Vice President and Director of DAS Healthcare and CEO of LLNS (now TBWA\WorldHealth New York). Prior to her 10 years at Omnicom, Sharon was Chief Digital Strategist at Grey Healthcare Group,  President of interactive agency Summit Grey, born out of The Summit Group, a company she co-founded. Previously, Sharon honed her talents at Medsite.com and SCP Communications.


In both 1997 and 2005, Sharon served as president of the Healthcare Businesswomen’s Association (HBA), the industry’s largest professional organization. Sharon currently sits on the board of the board of the HBA Metro Chapter, the Medical Advertising Hall of Fame, the Arthritis Foundation, Women Against Alzheimer’s, and Chairs the Executive Committee for the Coalition for Healthcare Communications Chairs the Executive Committee for the Coalition for Healthcare Communications,. In June 2014, the Women’s Venture Fund recognized Sharon with its “Highest Leaf Award,” for her strong business leadership and substantial contributions to the advertising and healthcare industries.


Consistently rated a trusted advisor to clients and a dedicated mentor to colleagues around the world, Sharon defines what it means to be a leader in today’s rapidly changing healthcare communications industry.


Sharon lives in New York City and is the proud mother of two sons, and can often be found cheering on the sidelines at a high school basketball game.