Legacy Information Systems: Issues and Directions

egacy information systems are typically the backbone of an organization’s information flow and the main vehicle for consolidating business information. They are thus mission critical, and their failure can have a serious impact on business.1 In fact, a LIS can be defined as “any information system that significantly resists modification and evolution.”2 They can cause host organizations several problems: ♦ LISs usually run on obsolete hardware that is slow and expensive to maintain. ♦ Software maintenance can also be expensive, because documentation and understanding of system details is often lacking and tracing faults is costly and timeconsuming. ♦ A lack of clean interfaces makes integrating LISs with other systems difficult. ♦ LISs are also difficult, if not impossible, to extend. Jesús Bisbal, Deirdre Lawless, Bing Wu, and Jane Grimson, TRINITY COLLEGE DUBLIN