This book constitutes the refereed proceedings of the Third International Conference on Distributed Computing and Internet Technology, ICDCIT 2006, held in Bhubaneswar, India in December 2006. The 24 revised full papers and 10 revised short papers presented together with 1 keynote address and 1 invited talk were carefully reviewed and selected from 200 submissions. Covering the main areas distributed computing, internet technology, system security, data mining, and software engineering the papers are subdivided in topical sections on wireless sensor network - routing and power control, localization and coverage, mobile adhoc networks - security and reliability, quality of service, grid and distributed computing, Web services and e-commerce, Web databases, data mining, and spatio-temporal databases.