News Release CACI International Inc · 1100 North Glebe Road · Arlington Virginia 22201

CACI Announces Interface Between SIMPROCESS^® and Business Process Management Software from ACI
Direct Data Exchange Saves Implementation Time and Money, Speeds Productivity Gains

Arlington, VA, December 13, 2005 — CACI International Inc (NYSE:CAI) announced today that it has developed an interface between its business process modeling and simulation software, SIMPROCESS^® 4.0, and the WorkPoint Business Process Management (BPM) Suite from ACI Worldwide. Providing a seamless transfer of data from business process modeling to BPM systems, the interface saves clients time and resources when implementing new process management systems. Both CACI and ACI expect to enhance their business opportunities with this new solution.

Launched in 1991 and based on CACI's early success in simulation programming, SIMPROCESS allows organizations to test alternatives to business processes before committing to them. The software is a key component of CACI's business in systems integration, business process reengineering, and modeling and simulation. SIMPROCESS is now being used to help reduce passenger wait times at airports, improve court efficiency, cut down on paper waste, and optimize emergency room staffing.

WorkPoint is a comprehensive BPM software suite that coordinates all aspects of a process — people, rules, tasks, and systems — into a cohesive whole. Representing over a decade of development and customer deployment, WorkPoint executes business processes from the simplest to the most complex.

By interfacing SIMPROCESS with the WorkPoint BPM suite, CACI is among the first solution providers to use practical simulation technology to manage today's rapidly changing business environment. Before the new interface, reengineering business processes required data to be developed in a business modeling tool like SIMPROCESS, then recreated in an automated process management system like WorkPoint. Now, however, SIMPROCESS data may be exported directly to WorkPoint for an initial workflow process design, and clients no longer incur the time and cost of manually inputting the SIMPROCESS data.

"The SIMPROCESS-ACI interface provides a seamless flow from business process modeling to automated process management," said Joe DeFee, CACI Senior Vice President. "This brings faster gains in productivity, reduces cost and risk, and ultimately provides a better way of doing business."

DeFee continued, "CACI was founded on simulation technology in 1962 and while our offerings have expanded significantly since then, we are still proud to be a leader in this field. We are pleased to work with ACI to continue expanding the range of SIMPROCESS applications for our clients and partners."

"There is a perfect match between the features of CACI's SIMPROCESS and those of ACI's WorkPoint," said Dale Van Stratten, Senior Vice President of Global Sales for ACI Worldwide. "We are extremely pleased to combine the SIMPROCESS technology with our WorkPoint product to offer an even more complete BPM solution. This combination of powerful capabilities will enhance our customers' ability to execute business processes effectively and efficiently."

About ACI Worldwide

ACI Worldwide is a leading international provider of solutions for consumer and wholesale payments and application infrastructure. ACI serves more than 800 customers in 84 countries including many of the world's largest financial institutions, retailers and payment processors. Visit ACI Worldwide at www.aciworldwide.com.

About CACI

CACI International Inc provides the IT and network solutions needed to prevail in today's new era of defense, intelligence, and e-government. From systems integration and managed network solutions to knowledge management, engineering, simulation, and information assurance, we deliver the IT applications and infrastructures our federal customers use to improve communications and collaboration, secure the integrity of information systems and networks, enhance data collection and analysis, and increase efficiency and mission effectiveness. Our solutions lead the transformation of defense and intelligence, assure homeland security, enhance decision-making, and help government to work smarter, faster, and more responsively. CACI, a member of the Russell 1000 and S&P SmallCap 600 indices, provides dynamic careers for approximately 9,500 employees working in over 100 offices in the U.S. and Europe. CACI is the IT provider for a networked world. Visit CACI on the web at www.caci.com.

There are statements made herein which do not address historical facts and, therefore could be interpreted to be forward-looking statements as that term is defined in the Private Securities Litigation Reform Act of 1995. Such statements are subject to factors that could cause actual results to differ materially from anticipated results. The factors that could cause actual results to differ materially from those anticipated include, but are not limited to, the following: regional and national economic conditions in the United States and the United Kingdom, including conditions that result from terrorist activities or war; changes in interest rates; currency fluctuations; failure to achieve contract awards in connection with recompetes for present business and/or competition for new business; the risks and uncertainties associated with client interest in and purchases of new products and/or services; continued funding of U.S. government or other public sector projects, based on a change in spending patterns, or in the event of a priority need for funds, such as homeland security, the war on terrorism or rebuilding Iraq; government contract procurement (such as bid protest, small business set asides, etc.) and termination risks; the results of government investigations into allegations of improper actions related to the provision of services in support of U.S. military operations in Iraq; the results of the appeal of CACI International Inc ASBCA No. 53058; individual business decisions of our clients; paradigm shifts in technology; competitive factors such as pricing pressures and/or competition to hire and retain employees (particularly those with security clearances); material changes in laws or regulations applicable to our businesses, particularly in connection with (i) government contracts for services, (ii) outsourcing of activities that have been performed by the government, (iii) competition for task orders under Government Wide Acquisition Contracts ("GWACs") and/or schedule contracts with the General Services Administration; and (iv) expensing of stock options; our own ability to achieve the objectives of near term or long range business plans; and other risks described in the company's Securities and Exchange Commission filings.

# # #