Contact email: Workshop organisers Rob van Glabbeek National ICT Australia Locked Bag 6016 University of New South Wales Sydney, NSW 1466 Australia Matthew Hennessy Department of Informatics University of Sussex Falmer, Brighton, BN1 9QN United Kingdom Webpage: http://www.cse.unsw.edu.au/~rvg/SOS2007 Special issue of Information & Computation

Aim: Structural operational semantics (SOS) provides a framework for giving operational semantics to programming and specification languages. A growing number of programming languages from commercial and academic spheres have been given usable semantic descriptions by means of structural operational semantics. Because of its intuitive appeal and flexibility, structural operational semantics has found considerable application in the study of the semantics of concurrent processes. Moreover, it is becoming a viable alternative to denotational semantics in the static analysis of programs, and in proving compiler correctness. Recently, structural operational semantics has been successfully applied as a formal tool to establish results that hold for classes of process description languages. This has allowed for the generalisation of well-known results in the field of process algebra, and for the development of a meta-theory for process calculi based on the realization that many of the results in this field only depend upon general semantic properties of language constructs. This workshop aims at being a forum for researchers, students and practitioners interested in new developments, and directions for future investigation, in the field of structural operational semantics. One of the specific goals of the workshop is to establish synergies between the concurrency and programming language communities working on the theory and practice of SOS. Moreover, it aims at widening the knowledge of SOS among postgraduate students and young researchers worldwide. Specific topics of interest include (but are not limited to): programming languages process algebras higher-order formalisms rule formats for operational specifications meaning of operational specifications comparisons between denotational, axiomatic and SOS compositionality of modal logics with respect to operational specifications congruence with respect to behavioural equivalences conservative extensions derivation of proof rules from operational specifications software tools that automate, or are based on, SOS. Papers reporting on applications of SOS to software engineering and other areas of computer science are welcome. History: The first SOS Workshop took place on the 30th of August 2004 in London as one of the satellite workshops of CONCUR 2004, and was attended by over 30 participants. Subsequently, SOS 2005 occurred on the 10th of July 2005 in Lisbon as a satellite workshop of ICALP 2005, and SOS 2006 on the 26th of August 2006 in Bonn as a satellite workshop of CONCUR 2006. Paper submission: We solicit unpublished papers reporting on original research on the general theme of SOS. Prospective authors should register their intention to submit a paper by uploading a title and abstract by Friday 6 April 2007. Papers should take the form of a pdf file in ENTCS format, whose length should not exceed 15 pages (not including an optional "Appendix for referees" containing proofs that will not be included in the final paper). We will also consider 5-page papers describing tools to be demonstrated at the workshop. Submissions from PC members are allowed. Proceedings: Preliminary proceedings will be available at the meeting. The final proceedings of the workshop will appear as a volume in the ENTCS series. Instructions for authors are here. Here is the stylefile entcsmacro.sty that authors should use in preparing the final version of their paper. Simultaneously with the workshop a special issue on Structural Operational Semantics of Information & Computation is being prepared, whose deadline for registering submissions has now passed. Authors that submitted a paper to this special issue may also submit a 15-page version of the same material for presentation at SOS 2007. Such contributions, when accepted for both I&C; and SOS07, will appear in the preliminary SOS07 proceedings that will be distributed at the meeting, but by default not in the ENTCS version. We may also decide to edit a further special issue of an archival journal, devoted to full versions of selected papers from the workshop not appearing in the special issue mentioned above. Important Dates: Submission of abstract: Friday 6 April 2007 Submission: Sunday 15 April 2007 Notification: Wednesday 9 May 2007 Final version: Friday 25 May 2007 Workshop: Monday 9 July 2007 Final ENTCS version: Friday 10 August 2007.