Software maintenance as an engineering discipline

Software maintenance can be transformed from the unmanageable, trial-and-error activity into a systematic engineering discipline through application of mathematics-based principles and practices that have wrought a similar transformation in software engineering. The mathematics provides rigorous techniques for converting unstructured programs into structured form, recovering program design documentation, and modifying and verifying programs. While these principles and practices are technical, the ultimate benefits are managerial, in a new level of predictability and control of maintenance operations to meet business needs