Allied World Assurance Company Holdings, AG (Allied World Switzerland), is a specialty insurance and reinsurance company that underwrites a diversified portfolio of property and casualty lines of business through offices located in Bermuda, Hong Kong, Ireland, Singapore, Switzerland, the United Kingdom and the United States. The Company has three business segments: U.S. insurance, international insurance and reinsurance. The U.S. insurance segment includes its direct insurance operations in the United States. The international insurance segment includes its direct insurance operations outside of the United States. The Company's reinsurance segment includes the reinsurance of property, general casualty, professional liability, specialty lines and property catastrophe coverages written by other insurance companies.