This book constitutes the thoroughly refereed post-proceedings of the 30th International Workshop on Graph-Theoretic Concepts in Computer Science, WG 2004, held in Bad Honnef, Germany in June 2004. The 31 revised full papers presented together with 2 invited papers were carefully selected from 66 submissions during two rounds of reviewing and improvement. The papers are organized in topical sections on graph algorithms: trees; graph algorithms: recognition and decomposition; graph algorithms: various problems; optimization and approximation algorithms; parameterized complexity and exponential algorithms; counting, combinatorics, and optimization; applications in bioinformatics and graph drawing; and graph classes and NP-hard problems.

The 35th International Workshop on Graph-Theoretic Concepts in Computer Science (WG 2009) took place at Montpellier (France), June 24–26 2009. About 80 computer scientists from all over the world (Australia, Belgium, Canada, China, Czech Republic, France, Germany, Greece, Israel, Japan, Korea, The Netherlands, Norway, Spain, UK, USA) attended the conference. Since1975,ithastakenplace20timesinGermany,fourtimesinTheNeth- lands, twice in Austria, as well as once in Italy, Slovakia, Switzerland, the Czech Republic, France, Norway, and the UK. The conference aims at uniting theory and practice by demonstrating how graph-theoretic concepts can be applied to various areas in computer science, or by extracting new problems from appli- tions. The goal is to present recent research results and to identify and explore directions of future research. The conference is well-balanced with respect to established researchers and young scientists. There were 69 submissions. Each submission was reviewed by at least three, and on average four, Program Committee members. The Committee decided to accept 28 papers. Due to the competition and the limited schedule, some good papers could not be accepted. Theprogramalsoincludedexcellentinvitedtalks:onegivenbyDanielKràlon “AlgorithmsforClassesofGraphswithBoundedExpansion,” the otherbyDavid Eppsteinon“Graph-TheoreticSolutionstoComputationalGeometryProblems.” The proceedings contains two survey papers on these topics.

The 28th International Workshop on Graph-Theoretic Concepts in Computer ? Science (WG 2002) was held in Cesky ́ Krumlov, a beautiful small town in the southern part of the Czech Republic on the river Vltava (Moldau), June 13–15, 2002. The workshop was organized by the Department of Applied Mathematics of the Faculty of Mathematics and Physics of Charles University in Prague. Since 1975, WG has taken place in Germany 20 times, twice in Austria and The Netherlands, and once in Italy, Slovakia, and Switzerland. As in previous years, the workshop aimed at uniting theory and practice by demonstrating how graph-theoretic concepts can be applied to various areas in Computer Science, or by extracting new problems from applications.The workshop was devoted to the theoretical and practical aspects of graph concepts in computer science, and its contributed talks showed how recent research results from algorithmic graph theory can be used in computer science and which graph-theoretic questions arise from new developments in computer science. Altogether 61 research papers were submitted and reviewed by the program committee. The program committee represented the wide scienti?c spectrum, and in a careful reviewing process with four reports per submission it selected 36papersforpresentationattheworkshop.Thereferees’commentsaswellasthe numerous fruitful discussions during the workshop have been taken into account by the authors of these conference proceedings.

The 18th International Workshop on Graph-Theoretic Concepts in Computer Science (WG '92) was held in Wiesbaden-Naurod, Germany, June 18-20, 1992. Itwas organized by the Department of Computer Science, Johann Wolfgang Goethe University, Frankfurt am Main. Contributions with original results inthe study and application of graph-theoretic concepts in various fields of computer science were solicited, and 72 papers were submitted and reviewed, from which 29 were selected for presentation at the workshop. The workshop was attended by 61 scientists from 16 countries. All 29 papers in the volume have undergone careful revision after the meeting, based on the discussions and comments from the audience and the referees. The volume is divided into parts on restricted graph classes, scheduling and related problems, parallel anbd distributed algorithms, combinatorial graph problems, graph decomposition, graph grammars and geometry, and modelling by graphs.

This volume presents the proceedings of the 20th International Workshop on Graph-Theoretic Concepts in Computer Science (WG '94), held in Herrsching, Germany in June 1994. The volume contains 32 thoroughly revised papers selected from 66 submissions and provides an up-to-date snapshot of the research performed in the field. The topics addressed are graph grammars, treewidth, special graph classes, algorithms on graphs, broadcasting and architecture, planar graphs and related problems, and special graph problems.

This book constitutes the thoroughly refereed post-workshop proceedings of the 27th International Workshop on Graph-Theoretic Concepts in Computer Science, WG 2001, held in Boltenhagen, Germany, in June 2001. The 27 revised full papers presented together with two invited contributions were carefully reviewed and selected from numerous submissions. The papers provide a wealth of new results for various classes of graphs, graph computations, graph algorithms and graph-theoretical applications in various fields.

This book constitutes the thoroughly refereed postproceedings of the 29th International Workshop on Graph-Theoretic Concepts in Computer Science, WG 2003, held in Elspeet, The Netherlands in June 2003. The 30 revised full papers presented together with 2 invited papers were carefully reviewed, improved, and selected from 78 submissions. The papers present a wealth of new results for various classes of graphs, graph computations, graph algorithms, and graph-theoretical applications in various felds.