This volume constitutes the refereed proceedings of the 18thInternational Symposium on Graph Drawing, GD 2010, held in Konstanz, Germany, during September 2010.The 30 revised full papers presented together with 5 revised short and 8poster papers were carefully reviewed and selected from 77 submissions.The volume also contains a detailed report about the 17th Annual GraphDrawing Contest, held as a satellite event of GD 2010. Devoted both totheoretical advances as well as to implemented solutions, the papers areconcerned with the geometric representation of graphs and networks andare motivated by those applications where it is crucial to visualizestructural information as graphs.