In this paper destructive shear testing was conducted by installing various sensors and instruments at critical locations of full-scale masonry walls. The purpose of this research was to determine through laboratory testing the effectiveness of new repair methods, used as a seismic retrofit of seriously cracked shear walls. Testing was performed on several different types of walls (brickwork and stone masonry). This experimental campaign is divided in two parts: FRCMs (Fiber Reinforced Cementitious Mortars) were initially employed to reinforce the walls and, after testing, stainless steel anchors and other materials have been used to “locally” repair the shear walls (crack sealing), and re-tested. The evaluation methods included the analysis of the lateral load capacities and stiffness characteristics, the failure modes, also implemented to detect any debonding phenomenon between the FRCM retrofit system and the masonry substrate. An evaluation of the overall structural behaviour of the walls before and after reinforcement, and again after the repair, is presented. The results indicate that several conditions have an effect on the efficiency of the composite repair. Shear-load capacity, shear strength and stiffness, wall ductility are considered in the analysis.