This volume comprises papers presented at the Third Isle of Thorns Conference on Finite Geometries and Designs. The papers explore the structure and associated incidence structures of Galois geometries, and their related automorphism groups. Among the main topics covered are generalized quadrangles and n-gons, groups acting on geometries, linear spaces, partial geometries, diagram geometries, non-Desarguesian planes, strongly regular graphs, and designs. This timely collection of articles is expertly presented and will be of interest to research workers and postgraduates in combinatorics, design theory, and finite geometries.