LONDON - Establishes Asian Branch Office in Hong Kong

Allied World Assurance Company Holdings, Ltd (NYSE: AWH) today announced
the opening of a branch office in Hong Kong in order to expand its operations
into Asia. Bill Cotter, Senior Vice President, Asia, will oversee all Asian
insurance operations, and be based out of the Hong Kong office. Initial
offerings include a variety of primary and excess professional lines and
general casualty products as well as a suite of accident & health products.
Allied World’s operations have received authorization from the Office of the
Commissioner of Insurance, Hong Kong, to conduct general business operations
in the specified classes.

Scott Carmilani, Allied World’s President and Chief Executive Officer
commented, “Allied World is expanding to Asia because we see great potential
in the region and in our ability to address growing risks for clients. As
companies seek insurance protection from a greater diversity of insurers, we
seek to distinguish ourselves with our expanded global expertise and our
capacity to handle claims in Asia locally, as well as our unique business
approach to insurance.”

Mr. Carmilani added, “We are excited to have Bill Cotter leading our
expansion into Asia. His years of international experience and stellar
reputation will aid us in building the relationships and service standards
needed to be successful in Hong Kong and throughout Asia.”

Prior to his position with Allied World, Mr. Cotter spent two years as
Chief Executive Officer of CIGNA Worldwide Life Insurance Company and CIGNA
Worldwide General Insurance Company, a Hong Kong subsidiary of CIGNA
International. Prior to that position, Mr. Cotter worked for AIG and its
affiliates for over 15 years, most recently as Chief Operating Officer of AIG
Small Business, Senior Vice President and Chief Underwriting Officer of
National Union Fire Insurance Company, and Regional Vice President, Southeast
Asia and Greater China Regions of American International Underwriters (AIU),
based in Hong Kong. Mr. Cotter has received Master of Business Administration
degrees from both London Business School and Columbia Business School, with a
Bachelor of Arts degree from Boston College.

Mr. Cotter noted, “I’m very excited to be a part of Allied World’s
strategic expansion into Asia. I’m confident in the abilities of the team we
have assembled in our Hong Kong office, and I look forward to the growth and
success of our company’s offerings in Asia moving forward. Hong Kong’s
favorable environment for business and its role as a leading centre for
finance globally make it the perfect location from which to spearhead Allied
World’s business in the region.”

Managing professional lines in Asia is Benjamin Howell, Vice President,
Professional Lines. Mr. Howell joined Allied World from AIG where he was Vice
President and Regional Manager, Greater China and Southeast Asia, Financial
Institutions and Crime. Managing general casualty is Echo Chen, Vice
President, General Casualty, who previously worked for AIG as Vice President
- Deputy Regional Manager, Liabilities Group, in Southeast Asia. Peter Ford,
Vice President, Claims and Business Development, joined Allied World from AIG
in Singapore where as Vice President and Regional Manager he managed a
cross-regional team handling casualty and financial lines claims across
Southeast Asia and China. Managing accident & health is Gene Raitt, Senior
Vice President Accident and Health and Director of Marketing, Asia. Mr. Raitt
was previously with American International Companies Worldwide in the
capacity of Executive Vice President & Chief Direct Marketing Officer.
Genevieve Balfour, General Casualty Underwriter, previously worked with
Allied World’s general casualty team in the company’s London and Dublin
offices and is now based in Hong Kong. Bessie Kwan manages the Hong Kong
office as Human Resources and Administration Director. Previously she was the
Assistant Vice President for Marsh Asia Pacific.

For more information on Allied World’s regional office in Hong Kong,
please contact Bill Cotter at william.cotter@awac.com.

About Allied World Assurance Company

Allied World’s office in Hong Kong is a branch office of Allied World
Assurance Company, Ltd, our Bermuda insurance and reinsurance company.

Allied World Assurance Company Holdings, Ltd, through its subsidiaries,
is a global provider of innovative property, casualty and specialty insurance
and reinsurance solutions, offering superior client service through offices
in Bermuda, the United States and Europe. Our insurance and reinsurance
subsidiaries are rated A (Excellent) by A.M. Best Company. For further
information on Allied World, please visit our website at www.awac.com.

Cautionary Statement Regarding Forward-Looking Statements

Any forward-looking statements made in this press release reflect our
current views with respect to future events and financial performance and are
made pursuant to the safe harbor provisions of the Private Securities
Litigation Reform Act of 1995. Such statements involve risks and
uncertainties, which may cause actual results to differ materially from those
set forth in these statements. For example, our forward-looking statements
could be affected by the ability to recognize the benefits of the Darwin
Professional Underwriters, Inc. acquisition; pricing and policy term trends;
increased competition; the impact of acts of terrorism and acts of war;
greater frequency or severity of unpredictable catastrophic events;
investigations of market practices and related settlement terms; negative
rating agency actions; the adequacy of our loss reserves; the company or its
subsidiaries becoming subject to significant income taxes in the United
States or elsewhere; changes in regulations or tax laws; changes in the
availability, cost or quality of reinsurance or retrocessional coverage;
adverse general economic conditions including those related to the ongoing
financial crisis; and judicial, legislative, political and other governmental
developments, as well as management’s response to these factors, and other
factors identified in our filings with the U.S. Securities and Exchange
Commission. You are cautioned not to place undue reliance on these
forward-looking statements, which speak only as of the date on which they are
made. We are under no obligation (and expressly disclaim any such obligation)
to update or revise any forward-looking statement that may be made from time
to time, whether as a result of new information, future developments or
otherwise.

For media enquiries, please contact:

Allied World Assurance Company
Faye Cook
VP, Marketing & Communications
Tel: +1-646-794-0543
Email: faye.cook@awac.com

For investor relations, please contact:

Allied World Assurance Company
Keith Lennox
Investor Relations Officer
Tel: +1-646-794-0750
Email: keith.lennox@awac.com

Source: Allied World Assurance Company Holdings, Ltd

Faye Cook, +1-646-794-0543, faye.cook at awac.com; Keith Lennox, +1-646-794-0750, keith.lennox at awac.com, both of Allied World Assurance