Abstract: Although Y2K was neither an accident nor an unanticipated challenge, the millennium debugging represented a watershed event for crisis response and management, and the range of effects remains relevant in 2004. Not only information systems professionals, but also leaders and professionals in every application area saw computer systems as subsystems of their areas of responsibility and accountability. The acknowledged dependence of government, healthcare, utilities, transportation, services, and communications on reliable information systems widened the circle of stakeholders for crisis prevention, response, and management. Emergency preparedness and broad systems approaches to disaster and contingency planning were enhanced by the ubiquitous multi-year Y2K effort. The author emphasizes the investments, learning, leadership, and commitment in information systems control that occurred as part of the prevention stage of crisis management as a result of Y2K. The simultaneity, high stakes, and ubiquity of the millennium crisis permanently altered the circle of players with vested interests in and responsibility for information systems control. From government agencies to households, users realized that the scope of information systems design and reliability must extend beyond computer engineers and information systems professionals to ensure the general good. © Proceedings ISCRAM 2004.