Examples of significant fusion materials R&D accomplishments are summarized for three general categories: (1) Fundamental studies of radiation-induced defects and their effects on material properties, (2) development of improved materials, and (3) development of novel experimental techniques. The fundamental studies R&D (incorporating multiscale modeling and associated experimental studies) is contributing to an improved understanding of the basic mechanisms of radiation damage. Combined studies on the microstructure and properties of irradiated materials are providing important contributions on mechanical deformation and fracture mechanisms. Steady progress is being made on the development of improved, radiation-resistant ferritic-martensitic steels, V alloys and SiC composites. Scoping investigations of refractory alloys (Mo,W alloys) and improved (nanocomposited) oxide dispersion strengthened ferritic steels are providing the technological groundwork for eventual implementation of these high-temperature alloys in future fusion systems. Progress is continuing on the development of innovative miniaturized mechanical property specimens, including fracture toughness and fatigue specimens. Examples of recently developed miniaturized specimen geometries are summarized. (C) 2002 Elsevier Science B.V. All rights reserved.