Zero Sum Trees: A Survey of Results and Open Problems

This is an expository paper which surveys results related to the recent confirmation of the zero-sum-tree conjecture by Z. Furedi and D. Kleitman. The author believes that trees play a major role in zero-sum Ramsey theory. He makes some observations that may lead in the far future to very general theorems and presents a collection of fifteen conjectures attributed to various people. Some of the conjectures have already appeared in print but most of them are new.