Analysis of anomalies reported during testing of a project can tell a lot about how well the processes and products work. Still, organizations rarely use anomaly reports for more than progress tracking although projects commonly spend a significant part of the development time on finding and correcting faults. This paper presents an anomaly metrics model that organizations can use for identifying improvements in the development process, i.e. to reduce the cost and lead-time spent on rework-related activities and to improve the quality of the delivered product. The model is the result of a four year research project performed at Ericsson. © 2008 Elsevier Inc. All rights reserved.