The volume ends with a chapter on "Structural and TransportProperties of Perfluorinated Ion-Exchange Membranes" by Dr.Richard S. Yeo and Professor Howard L. Yeager. The developmentof such membranes has revolutionized the electrochemical tech-nology of the chlorine-caustic industry and also has been of greatvalue in the engineering of water electrolyzers, organic preparationcells and some designs of fuel cells. This chapter is not only oftechnological interest in the above areas but deals in some detailwith fundamental problems of ion association, aggregation, mem-brane structure and ion transport in the solution-invaded, locallyhydrophobic medium which these polymers provide in membranes..