ADVISORY/ S1 Corporation Executive to Present `The Next Generation of eFinance' at the eFinance Conference & Exhibition.

Business/Technology Editors

e-finance New York 2001

ADVISORY...for Wed. (April 18)

--(BUSINESS WIRE)

S1 Corporation:

Who:    S1 Corporation, a leading global provider of eFinance
        solutions and services

What:   Presentation of "The Next Generation of eFinance," led by S1
        Corporation Chief Strategy Officer Charles W. Ogilvie

Where:  eFinance Conference & Exposition, New York Hilton & Towers,
        New York, NY

When:   Wednesday, April 18, 2001 from 1:45 - 2:45 p.m. EDT

Charles W. Ogilvie, chief strategy officer of S1 Corporation (Nasdaq: SONE), will examine three distinct technology strategies - in-house development, third-party solution integration and a combination of the two - that enable financial institutions to maximize customer relationships and generate revenue. The financial industry is in the midst of a transformation, with an influx of new and varied players in the market and the integration of the Internet. Ogilvie will discuss the critical importance of implementing an open eFinance-enabling engine, which can empower financial service providers to expand their services and delivery channels to create a compelling eFinance experience for customers. He also will evaluate the industry's move to fee orientation and how this business model will impact the way institutions sell products and assets in the future.

Ogilvie is responsible for defining and driving the execution of S1's corporate strategies. He helped launch S1, a leading global provider of eFinance solutions and services, as well as the world's first Internet-only bank, Security First Network Bank. Before joining S1, Ogilvie was the executive vice president of retail banking at Cardinal Bancshares, where he created and executed Cardinal's retail banking strategy. He started his 15-year career in financial services at the Memphis, Tennessee-based National Commerce Bancorporation (NCBC), one of the nation's leading retail banks, where he specialized in the alternative delivery of retail banking services.

The eFinance Conference & Exhibition is a high-level forum that addresses the issue of transformation of the traditional financial services firm into an entity capable of competing as a formidable e-business at both the retail and wholesale levels. This two-day conference, which runs April 17-18, is designed for senior executives who need to keep abreast of the issues surrounding the future of the financial services industry as technology and legislation continue to create an enormous number of challenges and opportunities.

About S1 Corporation

S1 (Nasdaq: SONE) is a leading global provider of innovative eFinance solutions and services that are centered on banking, brokerage and insurance. S1 is enabling financial service providers to create a complete Integrated eFinance Experience(TM) by delivering the tools necessary to meet the evolving demands of their customers across various lines of businesses, market segments and delivery channels. Through its Open eFinance Architecture(TM), S1 offers a broad range of applications that empower financial institutions to increase revenue, strengthen customer relationships and gain competitive advantage. Additionally, through the Company's professional services organization, S1 applications can be implemented in-house or hosted in an S1 Data Center. Additional information about S1 is available at http://www.s1.com.

Forward-Looking Statements

This press release includes statements and other matters which are forward-looking and subject to a number of risks and uncertainties that could cause actual results to differ materially from expectations. The statements contained in this release that are forward-looking are based on current expectations and are subject to risks and uncertainties that could cause actual results to differ materially from the results contemplated by the forward-looking statements. These risks and uncertainties include, but are in no way limited to:

-- the possibility that the anticipated benefits from our acquisition
transactions will not be fully realized;

-- the possibility that costs or difficulties related to our integration of
acquisitions will be greater than expected;

-- our dependence on the timely development, introduction and customers
acceptance of new Internet services;

-- rapidly changing technology and shifting demand requirements and Internet
usage patterns;

-- other risks and uncertainties, including the impact of competitive services,
products and prices, the unsettled conditions in the Internet and other
high-technology industries and the ability to attract and retain key personnel;
and

-- other risk factors as may be detailed from time to time in our public
announcements and filings with the SEC, including the Company's annual report
on Form 10-K for the year ended December 31, 2000.

In addition, nothing in the press release should be viewed as an update or comment on earlier forward-looking statements provided by S1 Corporation. As noted above, because actual results, performance or developments may differ materially from forward-looking statements, S1 will not update such statements over the course of future periods, except in the course of our reports under applicable laws.