This volume presents the proceedings of the SeventhInternational Workshop on Computational Geometry, CG'91,held at the University of Berne, Switzerland, March 21/22,1991.Computational geometry is not a precisely defined field.Often, it is understood as a nearly mathematical discipline,dealing mainly with complexity questions concerninggeometrical problems and algorithms. But often too, andperhaps increasingly, questions of more practical relevanceare central, such as applicability, numerical behavior andperformance for all kinds of input size. Topics consideredin CG'91 include:- Generalizations and applications of the Voronoi diagram- Problems with rectangular objects- Path determination- Moving objects- Visibility questions- Layout problems- Representation of spatial objects and spatial queries- Problems in higher dimensions- Implementation questions- Relations to artificial intelligence.