Open Problems

Open Problems - Collected by Jeff Erickson. Mainly in geometry.
compgeom.cs.uiuc.edu/~jeffe/open/

Open Problems from the Geometry Junkyard - Compiled by David Eppstein of the University of California at Irvine.
www.ics.uci.edu/~eppstein/junkyard/open.html

Open Problems on Discrete and Computational Geometry - Compiled by Jorge Urrutia, University of Ottawa.
www.csi.uottawa.ca/~jorge/openprob/

The Open Problems Project - A project to record open problems of interest to researchers in computational geometry and related fields.
www.cs.smith.edu/~orourke/TOPP/

Steiner Trees - Open Problems with Steiner Trees, maintained by Joe Ganley.
ganley.org/steiner/open.html