Locians, I found a simple C-GTK molecule viewer, but perhaps the only GTK+ molecule viewer. It comes from Eric Harlow's new book on GTK development. I have a link to the source code at the new Web site: http://129.63.144.25/ It compiled on my system, but I can't seem to display any molecules. If anyone gets it to work right, let me know. Greg, this might be something you want to take a close look at, since it deals with molecules and a GTK GUI. I can't find the license for it, but I think it is GNU GPL. Jeff -- J.W. Bizzaro Phone: 617-552-3905 Boston College mailto:bizzaro at bc.edu Department of Chemistry http://www.uml.edu/Dept/Chem/Bizzaro/ --