The 29th International Workshop on Graph-Theoretic Concepts in Computer Science (WG2003) was held in the Mennorode conference Centerin Elspeet, The Netherlands. The workshop was organized by the Centerfor Algorithmic Systems of the Institute of Information and Computing Sciences of Utrecht University. The workshop took place June 19–21, 2003. The 72 participants of WG 2003 came from universities and research institutes from 18 different countries and five different continents. The workshop looks back at a long tradition. It was first held in 1975, and has been held 20 times in Germany, twice in Austria, and once in Italy, Slo- kia, Switzerland, and the Czech Republic, and has now been held for the third time in The Netherlands. The workshop 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 applications. It is devoted to the theoretical and practical aspects of graph concepts in computer science. The goal is to present recent research results and to identify and explore - rections of future research. The talks given at the workshop 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.