News Release-- August 18, 2004

AON TODAY ISSUED THE FOLLOWING RELEASE

Aon and CSC Create Strategic Alliance to Deliver
Human Resources BPO Services

CHICAGO and EL SEGUNDO, Calif., Aug. 18, 2004 – Aon Corporation (NYSE: AOC) and Computer Sciences Corporation (NYSE: CSC) announced today that Aon Human Resources Outsourcing (HRO), a division of Aon Consulting Inc., has formed a strategic alliance with CSC to develop and deliver human resources business process outsourcing (HR BPO). Under the agreement, CSC will provide information technology (IT) application and infrastructure outsourcing services to support future HR BPO engagements.

“We are delighted to enter into this agreement with CSC,” said Gary Budzinski, president, Human Resources Outsourcing, Aon Consulting. “Our clients will no doubt benefit from the capabilities of both organizations as we team up on future human resource outsourcing engagements.”

“CSC’s expertise in business process excellence and our experience providing transformational IT services to global clients positions us well for this role,” said Mary Jo Morris, president of CSC’s Global Transformation Solutions organization. “Joining forces to deliver HR BPO services strengthens our ability to help clients achieve business goals.”

Aon HRO provides outsourcing services to manage clients’ business processes in the areas of benefits, compensation, payroll, recruitment, development and learning, and performance management. The organization provides outsourcing services to more than 400 organizations, servicing a combined total of more than 3.5 million employees.

About Aon

Aon Corporation (www.aon.com) is a leading provider of risk management services, insurance and reinsurance brokerage, human capital and management consulting, and specialty insurance underwriting. The company employs approximately 53,000 professionals in its 600 offices in more than 120 countries. Backed by broad resources, industry knowledge and technical expertise, Aon professionals help a wide range of clients develop effective risk management and workforce productivity solutions.

Aon Consulting is among the top global human resources consulting firms, with 2003 revenues of $1.185 billion and 7,500 professionals in 140 offices throughout the world. Aon Consulting delivers integrated consulting solutions to help clients with employee benefits, human resources outsourcing, compensation, communication and management consulting.

About CSC

Founded in 1959, Computer Sciences Corporation is a leading global IT services company. CSC’s mission is to provide customers in industry and government with solutions crafted to meet their specific challenges and enable them to profit from the advanced use of technology.

With approximately 90,000 employees, CSC provides innovative solutions for customers around the world by applying leading technologies and CSC’s own advanced capabilities. These include systems design and integration; IT and business process outsourcing; applications software development; Web and application hosting; and management consulting. Headquartered in El Segundo, Calif., CSC reported revenue of $14.9 billion for the 12 months ended July 2, 2004. For more information, visit the company’s Web site at www.csc.com.

Aon Safe Harbor Statement

This press release contains certain statements relating to future results, which are forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. These forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from either historical or anticipated results, depending on a variety of factors. Potential factors that could impact results include the general economic conditions in different countries around the world, fluctuations in global equity and fixed income markets, exchange rates, rating agency actions, resolution of regulatory issues, including those related to compensation arrangements with underwriters, pension funding, ultimate paid claims may be different from actuarial estimates and actuarial estimates may change over time, changes in commercial property and casualty markets and commercial premium rates, the competitive environment, the actual costs of resolution of contingent liabilities and other loss contingencies, and the heightened level of potential errors and omissions liability arising from placements of complex policies and sophisticated reinsurance arrangements in an insurance market in which insurer reserves are under pressure. Further information concerning the Company and its business, including factors that potentially could materially affect the Company’s financial results, is contained in the Company’s filings with the Securities and Exchange Commission.