Book excerpt: This volume of the Lecture Notes in Computer Science series contains all papers accepted for presentation at the 10th IFIP/IEEE International Workshop on Distributed Systems: Operations and Management (DSOM’99), which took place at the ETH Zürich in Switzerland and was hosted by the Computer Engineering and Networking Laboratory, TIK. DSOM’99 is the tenth workshop in a series of annual workshops, and Zürich is proud to host this 10th anniversary of the IEEE/IFIP workshop. DSOM’99 follows highly successful meetings, the most recent of which took place in Delaware, U.S.A. (DSOM'98), Sydney, Australia (DSOM'97), and L’Aquila, Italy (DSOM'96). DSOM workshops attempt to bring together researchers from the area of network and service management in both industry and academia to discuss recent advancements and to foster further growth in this ?eld. In contrast to the larger management symposia IM (In- grated Network Management) and NOMS (Network Operations and Management S- posium), DSOM workshops follow a single-track program, in order to stimulate interaction and active participation. The speci?c focus of DSOM’99 is “Active Technologies for Network and Service Management,” re?ecting the current developments in the ?eld of active and program- ble networks, and about half of the papers in this workshop fall within this category.