Nanotechnology is a cluster of emerging techniques that converge 'top-down' and 'bottom-up' from physics, chemistry and biology to the same nanoscale. Strictly speaking, nanotechnology is not yet a technology, because complete portfolios of available techniques to transform an idea into a commercial product hardly exist. The term 'nanotechnology' was introduced by Taniguchi in 1974 to refer to the increasingly precise (top-down) machining and finishing of materials and was popularized by Drexler during the 1980s by introducing the concept of molecular manufacturing. In that same period the first examples of nanoscale materials in the field of Solid State Ionics appeared, describing various syntheses, characterizations, and processing techniques in relation to new and improved properties which are to be ascribed, to a large extent, to the nanostructured microstructures. While nanotechnology is still in its infancy and concerted research efforts are needed before its full potential can be realized, it will, when this happens, form the next wave after solid-state technology and biotechnology. In the field of Solid State Ionics promising developments are reviewed in this paper. After a brief historical introduction to nanoscale materials, this paper will review the synthesis of nanostructured materials that have potential in relation to new solid-state electrochemical devices. Such electrochemical devices exhibit properties and applications otherwise unattainable. The future of nanostructured materials is discussed in the final section. (C) 2000 Elsevier Science B.V. All lights reserved.