After a brief introduction to the year 2000 (Y2K) software situation, this paper summarizes 10 options for handling the situation, two problems and 16 realities that distinguish Y2K work from other forms of software maintenance. Because it is basic to the case study, this paper then introduces a configuration management system, and briefly explains the 13 objectives for the one used by the organization reported. The Y2K case study coverage begins with a review of the project mission and background about the organization and its information systems environment. The key feature of what this organization did as part of its Y2K project was to build a supporting infrastructure. Of the eight tasks done by the project, only the eighth one was actually devoted to making the organization's software become Y2K compliant. The seven prior infrastructure tasks were: (1) install a single production module, (2) produce system documentation, (3) document all interface data, (4) populate a data dictionary, (5) analyse each production system, (6) produce and use viable JCL, and (7) produce run books. Besides making all the software Y2K compliant within schedule and budget at a cost below the USA national average, the project achieved nine other major benefits. This paper closes with a summary of a generic, successful, Y2K compliance process, and after some discussion, lists five lessons learned.