During the week of September 13, 1988 the Mathematical Sciences Research Institute hosted a four day workshop on Arboreal Group Theory. This volume is the product of that meeting. The program centered on the topic of the theory of groups acting on trees and the various applications to hyperbolic geometry. Topics include the theory of length functions, structure of groups acting freely on trees, spaces of hyperbolic structures and their compactifications, and moduli for tree actions.

Inhalt
Growth Functions of Amalgams.- On a Problem Raised by Alperin and Bass.- Group Actions on Non-Archimedean Trees.- A Counterexample to Generalized Accessibility.- Geodesic Currents On Negatively Curved Groups.- Pregroups and Lyndon Length Functions.- ?-Tree Actions are Not Determined by the Translation Lengths of Finitely Many Elements.- The Boundary of Outer Space in Rank Two.- Cohomological Dimension of Groups Acting on ?-Trees.- Branch Points and Free Actions on ?-Trees.- Axioms for Translation Length Functions.- Outer Automorphisms of Hyperbolic Groups and Small Actions on ?-Trees.- The Structure of Promislow's Continuous Free Product.- Foldings of G-Trees.