Maintenance is the process of changing existing software to modify software, either to add or enhance existing functions, or to fix errors (bugs). Maintenance is the dominant activity of many MIS organizations. An average of 70% of software budgets are devoted to maintenance (Swanson & Beath, 1989). Object-oriented programming (OOP) languages have been in used in research and, to a limited extent, in practice for approximately fifteen years. However, it was not until recently that OOP received considerable attention from the practitioner community. The object-oriented paradigm has been hailed because of its natural relationship to the real world, ease and speed of development, and ability to reuse objects in different programs. These capabilities are thought to produce major productivity gains over programming in 3GLs. However, given the importance of maintenance in the MIS organization, the decision to develop systems using OOP must include evaluation of the relative effectiveness of maintenance in that environment. Unfortunately, little research investigates the maintainability of applications written in object-oriented languages. The objective of this study is to examine the maintenance of systems developed in objected-oriented programming languages.