Before being translated in terms of physical, mechanical and chemical of materials, the initial step for eval-uating compatibility is interface creation. The thermodynamic properties of the materials as well as transport mechanisms – diffusion, capillary succion – at the interface and roughness of the concrete sub-strate are acting from the beginning and influencing the durability of the bond strength. A review of the main parameters influencing bond development is presented on the base of the equilibrium of the surface free energies of liquid and solid, applied to the concept of repair mortars, coating and hydrophobic treatments