This chapter describes CGAL at the time the ECG book was written. Constant and persistent improvement to the source code and the didactic manuals, review of packages by the Editorial board and exhaustive testing, through the years led to a state of excellent quality internationally recognized as an unrivalled tool in its field. At the time these lines are written, CGAL already has a foothold in many domains related to computational geometry and could be found in many academic and research institutes as well as commercial entities. Release 3.1 was downloaded more than 14.500 times, and the public discussion list counts more than 950 subscribed users.