This book contains Volumes 4 and 5 of the Journal of Graph Algorithms and Applications (JGAA) . The first book of this series, Graph Algorithms and Applications 1, published in March 2002, contains Volumes 1OCo3 of JGAA . JGAA is a peer-reviewed scientific journal devoted to the publication of high-quality research papers on the analysis, design, implementation, and applications of graph algorithms. Areas of interest include computational biology, computational geometry, computer graphics, computer-aided design, computer and interconnection networks, constraint systems, databases, graph drawing, graph embedding and layout, knowledge representation, multimedia, software engineering, telecommunications networks, user interfaces and visualization, and VLSI circuit design. The journal is supported by distinguished advisory and editorial boards, has high scientific standards, and takes advantage of current electronic document technology. The electronic version of JGAA is available on the Web at http: //jgaa.info/. Graph Algorithms and Applications 2 presents contributions from prominent authors and includes selected papers from the Dagstuhl Seminar on Graph Algorithms and Applications and the Symposium on Graph Drawing in 1998. All papers in the book have extensive diagrams and offer a unique treatment of graph algorithms focusing on the important applications. Contents: Approximations of Weighted Independent Set and Hereditary Subset Problems (M M Halldrsson); Approximation Algorithms for Some Graph Partitioning Problems (G He et al.); Geometric Thickness of Complete Graphs (M B Dillencourt et al.); Techniques for the Refinement of Orthogonal Graph Drawings (J M Six et al.); Navigating Clustered Graphs Using Force-Directed Methods (P Eades & M L Huang); Clustering in Trees: Optimizing Cluster Sizes and Number of Subtrees (S E Hambrusch et al.); Planarizing Graphs OCo A Survey and Annotated Bibliography (A Liebers); Fully Dynamic 3-Dimensional Orthogonal Graph Drawing (M Closson et al.); 1-Bend 3-D Orthogonal Box-Drawings: Two Open Problems Solved (T Biedl); Computing an Optimal Orientation of a Balanced Decomposition Tree for Linear Arrangement Problems (R Bar-Yehuda et al.); New Bounds for Oblivious Mesh Routing (K Iwama et al.); Connectivity of Planar Graphs (H de Fraysseix & P O de Mendez); and other papers. Readership: Researchers and practitioners in theoretical computer science, computer engineering, and combinatorics and graph theory."