NOVELTY - Reinforced ion-exchange membrane comprises a porous support matrix; and a polymeric film laminated on at least one side of the porous support matrix. The porous support matrix has no electric resistance as measured in the six compartment configuration. The polymeric film comprises a polymer functionalized with charged moieties in a degree of at least 5% (preferably 55-85)%. The polymeric film preferably comprises a blend of a functionalized polymer and a non-functionalized polymer. The porous support matrix has a thickness of 40-130 mu m. The polymeric film has a thickness of 8-11 mu m.    USE - As an ion-exchange membrane useful for electrodialysis and reverse electrodialysis applications (claimed), including desalination of water, desalination in food and pharmaceutical industry, separation of amino acids, production of salt, fuel cells, electric power generation and immediate and sustained release carriers for pharmaceuticals.    ADVANTAGE - The reinforced ion-exchange membrane provides an improved balance between a high permselectivity, a low electrical resistance, a good mechanical strength, and a high chemical stability as compared to the prior art. The use of polymeric film including a blend of a functionalized polymer and a non-functionalized polymer, results in a low resistance increase, providing very efficient reinforced ion exchange membranes with a high mechanical strength and a high permselectivity or ion selectivity. The reinforced ion-exchange membrane can be provided at relatively low costs. The properties, i.e., mechanical strength and ion-selectivity, of the polymer-based reinforced ion-exchange membranes and the production cost are very advantageous compared to reinforced ion-exchange membranes according to the prior art. Thin polymeric films with high selectivity and low resistance can be produced. The relative high ratio of polymeric film provides high selectivities and decreases the production costs of the membranes.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing the reinforced ion-exchange membrane involving providing a polymeric film and a porous support matrix; covering the polymeric film with a solvent for the polymeric film or a solution of a monomer of which the polymeric film is comprised; pressing the porous support matrix onto the polymeric film; and removing the solvent or solution to provide the reinforced ion-exchange membrane.