Modeling process and product quality during maintenance

This paper contains data demonstrating our recent experiences with measuring quality of evolving systems. Both process and product quality measures are discussed. This is an area in which more effective collaboration between practitioners and researchers would be of great value. We note that access to industrial software by researchers is often blocked by proprietary restrictions. When such restrictions can be eased, publication of analysis results is often hampered by the industrial owners and developers of the software. I believe that practice can be significantly aided by the data and results of broadly based research studies. Thus, closer collaboration in this area will benefit both communities.