The book constitutes the refereed proceedings of the First International Conference on Distributed Computing in Sensor Systems, DCOSS 2005, held in Marina del Rey, California, USA in June/July 2005.The 26 revised full papers presented were carefully reviewed and selected from 85 submissions; also included are the abstracts of 3 invited talks, 2 short papers, 9 invited poster abstracts, and 10 contributed abstracts.The papers address all current aspects of distributed computing issues in large-scale networked sensor systems, including systematic design techniques and tools, algorithms, and applications.