Various types of the proton-conducting composites and solid solutions based on the superprotonic acid salts are considered and some of their advantages over single-phase superprotonic crystal are discussed. Emphasis is given to structural composites on the basis of complex superprotonic salts and a new approach to the fabrication of composites containing an alumina matrix and superprotonic acid salts. (c) 2005 Elsevier B.V. All rights reserved.