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This volume contains the proceedings of the Fifth International Conference on Coordination Models and Languages (Coordination 2002), held in York, UK, 8–11 April 2002. Coordination models and languages close the conceptual gap - tween the cooperation model used by the constituent parts of an application and the lower-level communication model used in its implementation. Coordinati- based methods provide a clean separation between individual software com- nents and their interactions within their overall software organization. This se- ration, together with the higher-level abstractions o?ered by coordination models and languages, improve software productivity, enhance maintainability, advocate modularity, promote reusability, and lead to software organizations and arc- tectures that are more tractable and more amenable to veri?cation and global analysis. Coordination is relevant in design, development, debugging, maintenance, and reuse of all complex concurrent and distributed systems. Speci?cally, - ordination becomes paramount in the context of open systems, systems with mobile entities, and dynamically re-con?gurable evolving systems. Moreover, - ordination models and languages focus on such key issues in Component Based Software Engineering as speci?cation, interaction, and dynamic composition of components.

Traditionally, models and methods for the analysis of the functional correctness of reactive systems, and those for the analysis of their performance (and - pendability) aspects, have been studied by di?erent research communities. This has resulted in the development of successful, but distinct and largely unrelated modeling and analysis techniques for both domains. In many modern systems, however, the di?erence between their functional features and their performance properties has become blurred, as relevant functionalities become inextricably linked to performance aspects, e.g. isochronous data transfer for live video tra- mission. During the last decade, this trend has motivated an increased interest in c- bining insights and results from the?eld of formal methods – traditionally - cused on functionality – with techniques for performance modeling and analysis. Prominent examples of this cross-fertilization are extensions of process algebra and Petri nets that allow for the automatic generation of performance models, the use of formal proof techniques to assess the correctness of randomized - gorithms, and extensions of model checking techniques to analyze performance requirements automatically. We believe that these developments markthe - ginning of a new paradigm for the modeling and analysis of systems in which qualitative and quantitative aspects are studied from an integrated perspective. We are convinced that the further worktowards the realization of this goal will be a growing source of inspiration and progress for both communities.

This volume contains the proceedings of the 11th International Conference on Concurrency Theory (CONCUR 2000) held in State College, Pennsylvania, USA, during 22-25 August 2000. The purpose of the CONCUR conferences is to bring together researchers, developers, and students in order to advance the theory of concurrency and promote its applications. Interest in this topic is continuously growing, as a consequence of the importance and ubiquity of concurrent systems and their - plications, and of the scienti?c relevance of their foundations. The scope covers all areas of semantics, logics, and veri?cation techniques for concurrent systems. Topics include concurrency related aspects of: models of computation, semantic domains, process algebras, Petri nets, event structures, real-time systems, hybrid systems, decidability, model-checking, veri?cation techniques, re?nement te- niques, term and graph rewriting, distributed programming, logic constraint p- gramming, object-oriented programming, typing systems and algorithms, case studies, tools, and environments for programming and veri?cation. The?rst two CONCUR conferences were held in Amsterdam (NL) in 1990 and 1991. The following ones in Stony Brook (USA), Hildesheim (D), Uppsala (S), Philadelphia (USA), Pisa (I), Warsaw (PL), Nice (F), and Eindhoven (NL). The proceedings have appeared in Springer LNCS, as Volumes 458, 527, 630, 715, 836, 962, 1119, 1243, 1466, and 1664.

Physicalsystemswhichrightthemselvesafterbeingdisturbedevokeourcuriosity becausewe wantto understand howsuchsystemsareableto reactto unexpected stimuli. Themechanismsareallthe morefascinatingwhensystemsarecomposed of small, simple units, and the ability of the system to self-stabilize emerges out of its components. Faithful computer simulations of such physical systems exhibit the self-stabilizing property, but in the realm of computing, particularly for distributed systems, wehavegreaterambition. We imaginethat all manner of software, ranging from basic communication protocols to high-level applications, could enjoy self-corrective properties. Self-stabilizing software o?ers a unique, non-traditional approach to the c- cial problem of transient fault tolerance. Many successful instances of modern fault-tolerant networks are based on principles of self-stabilization. Surprisingly, the most widely accepted technical de?nition of a self-stabilizing system does not refer to faults: it is the property that the system can be started in any i- tial state, possibly an “illegal state,” and yet the system guarantees to behave properly in?nite time. This, and similar de?nitions, break many traditional approaches to program design, in which the programmer by habit makes - sumptions about initial conditions. The composition of self-stabilizing systems, initially seen as a daunting challenge, has been transformed into a mana- able task, thanks to an accumulation of discoveries by many investigators. - search on various topics in self-stabilization continues to supply new methods for constructing self-stabilizing systems, determines limits and applicability of the paradigm of self-stabilization, and connects self-stabilization to related areas of fault tolerance anddistributed computing.