Willis

New York, September 20, 2010 — Willis Group Holdings (NYSE: WSH), the global insurance broker, today announced that Celia Brown has been appointed Executive Vice President, Group Human Resources Director with responsibilities to drive the development of its global HR function and deliver world-class, strategic HR support to the company. Ms. Brown will report to Tim Wright, Chief Operating Officer, Willis Group, and will be based in New York. This appointment is effective immediately.

Ms. Brown has extensive global HR and legal experience. She was an executive of financial services company XL Group plc (and its predecessor NAC Re Corp) for 20 years in a series of senior roles. In 2006, she was appointed Head of Global HR and Corporate Relations, a role which she held until 2009. After leaving XL, Ms. Brown formed an independent management consultancy, providing human resources services to not-for-profit, corporate, and individual clients.

Welcoming Ms. Brown to Willis, Joe Plumeri, Willis Group Chairman and CEO, said, “Our people are our most important assets. Celia’s distinguished record in managing human capital in the insurance industry will strengthen our global HR function, ensuring that we grow, reward, develop, and manage our Associates in a manner that supports our culture and is responsive to the diverse needs of our businesses.”

Mr. Wright added, “Celia has helped guide companies like ours through cultural and organizational evolution. Her experience in designing global employment platforms will be invaluable in helping Willis meet its goals and objectives.”

Ms. Brown added, “I am excited to be joining Willis, with its great reputation for transparency and integrity, and once again to be a part of a dynamic, world-class organization that places the highest value on its people.”

Ms. Brown holds a law degree from the University of North Carolina School of Law, Chapel Hill, NC, and a Bachelor of Arts degree from Emory University, Atlanta, Georgia. She serves on the board of The Way to Work, an organization that provides education, vocational training, job placement, and mentoring to underprivileged and underserved New York City youth.

Willis Group Holdings plc is a leading global insurance broker. Through its subsidiaries, Willis develops and delivers professional insurance, reinsurance, risk management, financial and human resource consulting and actuarial services to corporations, public entities and institutions around the world. Willis has more than 400 offices in nearly 120 countries, with a global team of approximately 17,000 employees serving clients in virtually every part of the world. Additional information on Willis may be found at www.willis.com.