The papers in this volume show the lively variety of topics and methods in automated deduction in geometry, and their applicability to different branches of mathematics as well as to other sciences and technologies. The book is made up of the thoroughly refereed post-proceedings of the 6th International Workshop on Automated Deduction in Geometry, ADG 2006, held at Pontevedra, Spain, in 2006. There are a total of 13 revised full papers selected from a number of submissions.