A comparison is made between the two modes of repair of internal cracks in concrete: resin injection, which is done manually after cracking, and self-repair in which the adhesive for repair is already present in the matrix at the time the cracking occurs. The purpose of the project was to study the effect of various adhesives used for self-repair on the repair of concrete considering factors such as stress transfer capability, varying crack width, and damping. Different release modes and a similar range of adhesives with varying modulus of elasticity were used in the experiments. The purpose for varying the modulus of elasticity was to investigate the penetration ability of the adhesives. It is known that an adhesive's relative stiffness is directly related to its modulus of elasticity, and consequently, its ability to repair cracks is influenced by this factor. Finally, a comparison was made with studies undertaken by others on resin injection repair regarding stress, strain, and modulus of elasticity. Self-repair adhesives with higher modulus of elasticity (stiffer adhesives) transferred stresses well across the crack width allowing the crack to sustain as much, if not more, as the original loading as measured by specimen strength. The adhesives with lower modulus of elasticity (more flexible adhesives) also transferred the stresses.