Taking into account the various forms of fretting-corrosion manifestation, on the example of the contact of titanium alloy ВТ8 with structural alloys based on Al, Cu, Mg and Fe and with the same material, an attempt is made to develop a complex approach to the selection of compatible materials of friction pairs. According to the research results, the quantitative indicators of fretting wear of friction-pair materials are defined, and the regularities of mutual influence of the nature and properties of the materials on the friction-wear parameters of the tribosystem are analysed. For tribosystems, where the loss of functionality is associated with the accumulation of wear products, a calculation method for determining the compatibility of materials based on the volume-increment coefficient of the materials within the tribocontact zone is proposed.