It is our pleasure to introduce this volume of proceedings of the Joint Conference on Knowledge-Based Software Engineering 2006 (JCKBSE'06) held in August 28–31, 2006 in Tallinn, Estonia. The JCKBSE is a traditional biannual conference focused at applications of artificial intelligence in software theory and practice. This conference has become an international event with talks submitted from sixteen countries this year. After careful reviewing, 37 talks from thirteen countries have been accepted. Traditionally for JCKBSE, most of talks are from Japan, the second place belongs to Russia. The talks address the research in theoretical foundations, practical techniques, software tools, applications and/or practical experiences in knowledge-based software engineering. The topic of the present conference includes a new field: research in web services and semantic web. This is a rapidly developing research area promising to give excellent practical outcome, and interesting for theoretically minded as well as for practically minded people. The largest part of talks belongs to a traditional area of applications of artificial intelligence methods to various software engineering problems. Another traditional section of the conference is application of intelligent agents in software engineering. A separate section is devoted to interesting applications and special techniques related in one or another way to the topic of the conference.

We would like to thank, first of all, the authors of submitted papers. Their research is a justification for a conference in this field of science. We express our gratitude to members of the Program Committee of the conference for their thorough work in reviewing the submissions. The work of program committee and its chairs has been greatly facilitated by EasyChair that is an excellent tool developed and managed by Andrei Voronkov, to whom we wish to express our gratitude for his kind support.

Enn Tyugu and Takahira Yamaguchi, JCKBSE'06 program co-chairs