A conceptual model of software maintenance

Four distinct maintenance systems are studied and synthesised: the SEI quality framework and three industrial systems belonging to ABB, Ellemtel, and Ericsson. The goal is to validate the SEI framework, and to build a "state of the practice" conceptual model of the most fundamental software maintenance concepts. This model can help understand the underlying conditions for managing software maintenance. It can provide guidance to organisations in the process of building or improving their maintenance systems. It also constitutes a common basis for communication, for reasoning about software quality, and for building quality and maintenance models.