The resin-modified glass ionomer materials are hybrid materials of traditional glass ionomer cement with a small addition of light-curing resin, and hence exhibit properties intermediate to the two, with some characteristics superior to conventional glass ionomer materials. Generally, they have the advantages of both such as adhesion to tooth structure, esthetics, fluoride release and rapid hardening by visible light. Issues surrounding other physical properties, such as the mechanism of adhesion, sensitivity to water, long-term wear and strength, need to be addressed and substantiated. There are other considerations, which are not features of the conventional materials, but are of importance with the resin-modified glass ionomer cements i.e. light-curing, which require further research to provide evidence of their behavior. The future for this group of materials is unknown, but the currently available materials appear to be promising.