This volume contains contributions to the 17th Internationalworkshop on Graph-Theoretic Concepts in Computer Science(WG '91) held in Southern Bavaria in June 1991. These annualworkshops are designed to bring together researchers usinggraph-theoretic methods to discuss new developments relatingto or emerging from a diversity of application fields. The topics covered in this volume include: tree-relatedproblems, graph grammarsand rewriting, complexity,computational geometry, parallel algorithms, vertexorderings, path-oriented algorithms, applications to VLSI,and disjoint cycle problems.