My main research interest has centred around the interaction of discrete groups, in the form of fundamental groups of finite complexes, and geometric objects of various sorts.  My work can be classified under the following headings; homotopy classification of low dimensional complexes; aspherical manifolds; group actions on Euclidean space; space form problems; surface fibrations and poly-Fuchsian groups; homotopy theory of Kähler manifolds; arithmetic groups; Lie algebras and supersymmetry; invariant theory.

My main current interest is the homotopy classification of two and three dimensional complexes.