The workshop was held in conjunction with the OntoWeb3 meeting, and was hosted by SIG2 (Languages and Standards) of the OntoWeb Network. It brought together 15 researchers who presented their work on rules and rule markup languages with about 20 further participants in the audience.
Rule markup languages, that allow to express business rules as modular, stand-alone units in a declarative way, and to publish them and interchange them between different systems and tools, will play an important role for facilitating business-to-customer (B2C) and business-to-business (B2B) interactions over the Web. The workshop was a forum for presenting research on various kinds of rules that can be used in various applications and in connection with the Web. The RuleML initiative makes a distinction between four main categories of rules: integrity rules (constraints), derivation rules, reaction rules and transformation rules.
In his keynote talk, Sharma Chakravarthy, from the University of Texas at Arlington, pointed out how pervasive the Event-Condition-Action (ECA) rule paradigm is for today's computing technologies. ECA rules, which are a kind of reaction rules, can be used for integrity maintenance and for defining alert policies in all kinds of information stores, such as SQL databases and XML document repositories. They can be used to implement business rules in e-business applications and to support workflow management.
A very different type of rule was the focus of an invited presentation  by Sebastian Schaffert, co-authored by Francois Bry, from the University of Munich, Germany. Their XML transformation rule language Xcerpt, competing with W3C's XQuery, allows the flexible querying and transformation of XML documents.
There were two technical contributions on markup languages for ECA rules [3,6], one about the issue of marking up integrity rules , two about derivation rules [1,8], and two about transformation rules [9,14]. The other talks presented applications [2,4,5,10,11] and rules in data mining [12,13].
The workshop organisers hope to be able to publish post-workshop proceedings. When concluding the workshop, there was a general feeling that it was a great success and should be continued as a workshop series in the future.
The workshop proceedings have now been published online at http://CEUR-WS.org/Vol-60.
List of Presentations
 SweetJess: Translating DAMLRuleML to JESS Benjamin Grosof, Mahesh D. Gandhe, Timothy W. Finin http://www.soi.city.ac.uk/~msch/conf/ruleml/grosof.pdf
 A System for Querying and Viewing Business Constraints Mizuho Iwaihara, Masayuki Kozawa, Jun Narazaki, Yahiko Kambayashi http://www.soi.city.ac.uk/~msch/conf/ruleml/iwaihara.pdf
 The situation manager rule language Asaf Adi and Opher Etzion http://www.soi.city.ac.uk/~msch/conf/ruleml/adi.pdf
 OntoAgent: A platform for the declarative specification of agents Andreas Eberhart http://www.soi.city.ac.uk/ msch/conf/ruleml/eberhart.pdf http://www.soi.city.ac.uk/~msch/conf/ruleml/adi.pdf
 Representing Agent Contracts with Exceptions using XML Rules, Ontologies, and Process Descriptions Benjamin Grosof and Terrence Poon http://www.soi.city.ac.uk/~msch/conf/ruleml/grosof2.pdf
 ARML: an active rule mark-up language for heterogeneous active information systems E.S. Chu, Insuk Park, Soon J. Hyum, Myungchul Kim http://www.soi.city.ac.uk/~msch/conf/ruleml/park.pdf
 A Markup Language for ORM Business Rules Jan Demey, Mustafa Jarrar and Robert Meersman http://www.soi.city.ac.uk/~msch/conf/ruleml/jarrar.pdf
 A Nonmonotonic Rule System using Ontologies Grigoris Antoniou http://www.soi.city.ac.uk/~msch/conf/ruleml/grigoris.pdf
 An Equivalent-Tranformation-Based XML Rule Language Chutiporn Anutariya, Vilas Wuwongse, Vichit Wattanapailin http://www.soi.city.ac.uk/~msch/conf/ruleml/kay.pdf
 UML as knowledge acquisition frontend for Semantic Web configuration knowledge bases A. Felfernig, G. Friedrich, D. Jannach, M. Stumptner, M. Zanker http://www.soi.city.ac.uk/~msch/conf/ruleml/felfernig.pdf
 A use case for DAML+OIL: a knowledge base in a clinical domain M. Taboada, M. Arguello, D. Martinez, J. Des, J. Mira http://www.soi.city.ac.uk/~msch/conf/ruleml/chus.pdf
 An inductive approach to assertional Mining of Web Ontology Revision Chieko Nakabasami http://www.soi.city.ac.uk/~msch/conf/ruleml/nakabasami.pdf
 Content-based Retrieval of Analytical Reports Vaclav Lin, Jan Rauch, and Vojtech Svatek http://www.soi.city.ac.uk/~msch/conf/ruleml/lin.pdf
 A gentle introduction to Xcerpt, a rule-based query and transformation language for XML Sebastian Schaffert and Francois Bry http://www.soi.city.ac.uk/~msch/conf/ruleml/bry_schaffert.pdf