Thomas Harrison is Chairman and Chief Executive Officer of Diversified Agency Services (DAS), the world’s largest holding group of marketing services companies. A division of the Omnicom Group, DAS provides a broad range of marketing communications services including public relations, crisis management, branding, sales promotion, customer relationship management and specialty communications such as healthcare advertising for some of the largest global brands. With over 5000 worldwide clients, the DAS division has annual revenues of almost $5.0 billion and is the largest unit within Omnicom, itself the world’s largest advertising holding company.

Under Harrison’s watch the DAS division has more than quadrupled in size and now accounts for almost 60% of the total revenues of Omnicom. He has acquired and heads a list of companies that are the most influential in their areas, particularly in public relations, relationship marketing, branding and healthcare communications. He has developed not only the largest group of specialized agencies but the most diverse as well.

Harrison’s multi-faceted career brought him to Omnicom in 1992 when the firm he co-founded, Harrison & Star Business Group, the most successful and rapidly growing agency in the healthcare industry at the time, was acquired. Harrison served as Chairman of the Harrison & Star Group and Chairman of Diversified Healthcare Communications, a group of eight healthcare agencies within Omnicom, until his appointment as President of DAS in 1997. He was named Chairman and Chief Executive of DAS in 1998.

With an advanced degree in cell biology and physiology, Harrison began his business career at Pfizer Laboratories as a sales representative and left Pfizer as marketing director. He then joined a mid-sized healthcare advertising agency for six years before starting his own company, The Harrison & Star Business Group. While at the helm he started a healthcare advertising agency, a medical education company, a direct-to-consumer healthcare company and a medical PR group as well as acquiring a managed care consultancy.

Harrison serves on a number of prestigious boards. He is a member of the Executive Committee of the Montefiore Hospital and is a Fellow of the New York Academy of Medicine. He serves as a board member of the New York Chapter of the Arthritis Foundation. Harrison is a board member for ePocrates, a healthcare information company, The Morgans Hotel Group and several marketing services companies. He was President of a local Westchester County School Board and Chairman and Founder of the not-for-profit education foundation in that Westchester School District. He is a member of the President’s council at Tulane University School of Medicine. He has served as co-chairman of the New York Chapter of the U.S. Olympic Committee and raised substantial funding to support U.S. Olympic Athletes. He has been honored by Long Island College Hospital, The Children’s Hospital at Montefiore and by The Lymphoma Foundation. He is a frequent speaker at business forums and at universities on the subject of entrepreneurialism, business strategies and the "Secrets to Success". Harrison has spoken at West Virginia University where he did his graduate research and where he was recognized with the 2006 Distinguished Alumni Award. Harrison is being bestowed with an Honorary PhD from West Virginia University, the highest honor an American University grants to an individual. He is being honored by Mount St. Vincent’s College, where he has also been a keynote speaker. He is being honored by New York’s Health and Hospital Services in the spring of 2007. He was keynote speaker at The McGraw Hill Medical Publishers Annual Awards program and at a recent Management Conference of Healthcare Communications specialists, and talked to agency CEOs at an advertising industry forum about the future of advertising agencies, marketing services and ideation.

Harrison is the author of the recently published book INSTINCT: Tapping Your Entrepreneurial DNA to Achieve Your Business Goals, published by Warner Business Books. Harrison has appeared on CNBC, CNNI, Bloomberg and Forbes.com discussing the book. He can be found on the Enterprise Leadership podcast as well as other podcasts. Harrison also lectures at business schools and schools of entrepreneurialism on topics discussed in INSTINCT.

Harrison is a member of the New York University Campaign Steering Committee, is Chairman of the Dean’s Council at The Steinhardt School of Education at NYU and is a Trustee at The Kent School, a New England preparatory school.