Paper gives a good overall picture on research done in the area of engineering changes. I recommend it to everybody who has done or is interested in doing work in this area. It gives definitions to engineering change, and engineering process. It looks at the different types of changes (initiated, emergent), classifications (by urgency, by timing, late). Paper talks about the effects of changes and the rule of 10 (the implementation cost increases by a factor 10 between different phase of the design process). The nature of products is also discussed (product complexity, architecture, degree of innovation). In the end tools and strategies to cope with changes are presented.