The adhesive interaction between salt-treated polyester fibres and elastomeric matrices has been studied. Two types of approaches have been used to predict the impact of the salt treatment on the interaction between both jointing partners. First of all xi-potential measurements have been used to characterize the interactions between fibre and matrix. Changes in the surface composition of salt-treated fibres were investigated by electrokinetic measurements using the streaming potential. Zeta potential of latex were determined using the electrophoresis method. The second approach is the characterization of adhesion by the interfacial shear strength determined from the single-fibre pull out test. We compared results issued from the two methods used during this study.