Just like the previous workshop at VLDB 1999 in Edinburgh, the purpose of this workshop is to promote telecom data management as one of the core research areas in database research and to establish a strong connection between the telecom and database research communities. As I wrote in the preface of those proceedings, data management in telecommunications is an interesting area of research given the fact that both service management and service provisioning are very data intensive, and pose extreme requirements on data management technology. Given the feedback on the previous workshop we decided to keep the same program set-up for this workshop: an invited speaker, a collection of research papers, and a panel discussion. We received 18 good quality papers from which we selected 12 to construct a very interesting program. The program has been divided into four sections. The first section focuses on CDR data warehouse and data mining technology. Data warehousing and data mining around customer usage data remains an important area of interest for telecommunication operators. The growing competition, especially in the mobile market, means that operators have to put more effort into customer retention and satisfaction. The second section focuses on performance issues around databases in telecommunication. Since telecommunication databases are characterized by their extreme requirements, for example in terms of volumes of data to be processed or response times, high volume data management and embedded and real-time data management are key aspects of the telecommunication data management problems in today’s operational environments.