Digital engineering methods and systems are vitally important for performing key technical and business functions of global enterprises in a distributed and collaborative manner. The product design and engineering systems are gradually being developed to include a variety of tools for DfX, as well as incorporate aspects of digital manufacturing. Digital Enterprise Technology: Perspectives and Future Challenges, an edited volume, contains accepted chapters presented at the 3rd, CIRP sponsored International Conference in Digital Enterprise Technology (DET'06), held in Setúbal, Portugal, September 2006. DET 2006 follows on the success of the two previous meetings held in Durham, UK and Seattle, USA, in 2002 and 2004 respectively. The chapters presented in this book are contributed by world class leaders in the field. This volume includes relevant examples of current state-of-art in the development and use of systems and methods for the digital modelling of global development and realization processes in the context of life cycle management.