ACI Worldwide Guarantees Adoption of Electronically Delivered Statements and Bills; ACI e-Courier Software Flexibility is Catalyst for Guarantee.

Business Editors/High Tech Writers

OMAHA, Neb.--(BUSINESS WIRE)--Dec. 12, 2001

ACI Worldwide (Nasdaq:TSAI), a leading international provider of enterprise e-payment solutions, announces the launch of a guaranteed adoption program in conjunction with its ACI e-Courier solutions. With this program, ACI Worldwide guarantees that companies using its document delivery software, ACI e-Courier(TM) and/or e-Courier for Billing(TM), will achieve a 20 percent adoption rate within one year of production go-live.

"With ACI e-Courier solutions, companies can offer their customers and business partners electronic document and information delivery services with unparalleled convenience and flexibility," said Don McCormick, COO of ACI's e-Courier business unit. "Giving customers what they want, the way they want it, while minimizing required changes in behavior is what will lead to high adoption rates. We believe our solution reduces the risk of low adoption by broadening choices and minimizing behavioral change. To prove this assertion in the marketplace, we are willing to provide this additional incentive and partner with our customers to minimize their risk."

ACI e-Courier enables companies to electronically generate notices and alerts, summary information with URL links, data records or files, and complete paper document replacements, then securely deliver or present them to customers through a broad range of delivery channels and devices. Consumers and businesses can receive everything from statements and bills, to invoices and other documents securely and safely via e-mail, Web sites, consolidation services, aggregator services, mobile telephones, personal digital assistants (PDAs), Web TV and other open network channels and devices.

ACI's program is targeted at companies globally that license the e-Courier solutions between now and March 31, 2002. If after one year of production service, the company has not achieved a 20 percent adoption rate among customers with online access, ACI will provide the company a credit equal to the license fees paid for the solution.

ACI e-Courier and e-Courier for Billing are two of the products in ACI's e-series portfolio of secure electronic commerce software and services. The e-Courier solutions give companies the ability to create and deliver interactive and content-rich electronic statements, bills, and other documents securely to their customers via multiple delivery channels with the expressed intent of eliminating paper. ACI e-Courier for Billing provides electronic payment capabilities for billing specific applications.

About ACI Worldwide

Every second of every day, consumers are initiating electronic payment transactions--getting cash at ATMs, using debit and credit cards to make purchases in stores and on the Internet, banking by phone and PC, paying bills online. Twenty billion times a year, ACI software is used to process these transactions, powering the world's online payment systems. ACI was founded in 1975 and pioneered the development of applications and networking software for online transaction processing. Today more than 530 customers in 79 countries use ACI supplied software. Visit ACI Worldwide on the Internet at www.aciworldwide.com.

Any statements in this press release regarding projected results are preliminary and "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. In addition, this press release may contain other forward-looking statements including statements regarding Transaction Systems Architects, Inc.'s ("TSA"), its subsidiaries or third parties' expectations, predictions, views, opportunities, plans, strategies, beliefs, and statements of similar effect. The forward-looking statements in this press release are subject to a variety of risks and uncertainties. Actual results could differ materially. Factors that could cause actual results to differ include but are not limited to the following.

The success of TSA, or any of its subsidiaries, entering into a new distribution or partnering arrangement depends on numerous factors including the acceptance of the distributed products or services by TSA's existing customer base and integration of the products and services into TSA's marketing efforts, the quality of the products or services as perceived after use by TSA's customers, and the degree of competition from competitive products or service providers.

TSA's business is concentrated in the banking industry, making it susceptible to a downturn in that industry.

TSA is subject to risks of conducting international operations including: difficulties in staffing and management, reliance on independent distributors, fluctuations in foreign currency exchange rates, compliance with foreign regulatory requirements, variability of foreign economic conditions, and changing restrictions imposed by U.S. export laws.

Fluctuations in quarterly operating results may result in volatility in TSA's stock price. No assurance can be given that operating results will not vary. TSA's stock price may also be volatile, in part due to external factors such as announcements by third parties or competitors, inherent volatility in the high-technology sector and changing market conditions in the industry.

For a detailed discussion of these and other risk factors, interested parties should review TSA's filings with the Securities and Exchange Commission, including Exhibit 99.01 to TSA's Annual Report on Form 10-K for the fiscal year ended September 30, 2000.