IntroductionGraph Transformation and Visual Modeling Techniques - GT-VMT 2001After the success of last year in Geneva (Switzerland), also this year ICALP hosts the International Workshop on Graph Transformation and Visual Modeling Techniques (GT-VMT), held in Crete (Greece) on July 12 and 13, 2001.The success of visual modeling techniques is widely recognized in many areas and in particular in software engineering: structured analysis, Petri nets ans Statecharts are only a few “classical” notations that exploit diagrammatic reasoning to render concepts and ideas. Graphical notations are assuming even increasing importance in software engineering with the wide adoption of UML (Unified Modeling Language), as the standard notation for developing almost any kind of software systems, and coordination languages for describing software architectures and distributed systems.All these languages come with clear and well-defined graphical syntaxes, but lack precise approaches for formalizing these concepts and reasoning on their semantics. The last-year workshop has already proven the suitability of Graph Grammars and Graph Transformation to express these concepts; this year, the workshop aims at fostering their central role and disseminating their capabilities and potentialities in other communities, which already use graphs and diagrammatic reasoning, but do not master the necessary technical foundations. This is why the workshop aims at making “technology providers”, that is, experts in graphs and graph transformation, work together with “potential customers”, that is, users of diagrammatic reasoning. It is a good opportunity to try to collate the different viewpoints and find sound solutions to well-known problems.The Program Committee selected twelve contributions by researchers from several different countries: Belgium, Brazil, France, Germany, Italy, Japan, and USA. Selected contributions are both methodological and practical, that is, they try to both improve available technology and apply it to concrete examples. The program includes also two invited talks by Hartmut Ehrig (TU Berlin, Germany) and Andy Schuerr (University of the German Federal Armed Forces, Germany).The organizers want to thank Hartmut Ehrig for proposing to organize the workshop, the whole Program Committee for their hard and valuable work, and Christos D. Zaroliagis for the constant support provided while organizing the meeting.July 2001 Gabriele Taentzer, Luciano Baresi, and Mauro PezzéProgram Committee•Luciano Baresi (Politecnico di Milano, Italy)•Andrea Corradini (University of Pisa, Italy)•Gregor Engels (University of Paderborn, Germany)•Robert France (Colorado State University, USA)•Reiko Heckel (University of Paderborn, Germany)•Hans-Joerg Kreowski (University of Bremen, Germany)•Francesco Parisi Presicce (University of Roma, Italy)•Mauro Pezzé (University of Milano, Bicocca, Italy)•Gregor Rozenberg (Universiteit Leiden, Netherlands)•Gabriele Taentzer (TU Berlin, Germany)