This volume gives the proceedings of WG '90, the 16th in a series of workshops. The aim of the workshop series is to contribute to integration in computer science by applying graph-theoretic concepts. The workshops are unusual in that they combine theoretical aspects with practice and applications. The volume is organized into sections on: - Graph algorithms and complexity, - VLSI layout, - Multiprocessor systems and concurrency, - Computational geometry, - Graphs, languages and databases, - Graph grammars. The volume contains revised versions of nearly all the papers presented at the workshop. Several papers take the form of preliminary reports on ongoing research.