Unreinforced masonry load-bearing walls constitute the construction system of a considerable percentage of existing residential buildings in Egypt. Rehabilitation of such structures may require making openings of windows and doors in the walls, which decreases the load carrying capacity of the walls and presents threats for the safety of the structure. In this case, strengthening is required in order to enable making such openings, by increasing the capacity of the walls and reducing crack propagation.Unreinforced masonry load-bearing walls constitute the construction system of a considerable percentage of existing residential buildings in Egypt. Rehabilitation of such structures may require making openings of windows and doors in the walls, which decreases the load carrying capacity of the walls and presents threats for the safety of the structure. In this case, strengthening is required in order to enable making such openings, by increasing the capacity of the walls and reducing crack propagation. The objective of the present research is investigation of the effectiveness of different strengthening techniques so as to enable making openings in unreinforced masonry walls. An experimental program is conducted where 18 masonry walls of dimensions 1200x1200x110 mm were built using clay brick units (250x120x60 mm) and cement mortar. Different strengthening were made on the perimeter of the intended opening such as glass reinforced polymers sheets and strips, near-surface mounted steel bars and ferro-cement layer, each technique is applied on three walls. In-plane loading is applied vertically on the top of the walls up to working load level, an opening having dimensions 400x800 mm is made in the wall, then the load is gradually increased until failure. The experimental results of load-displacement behavior, ultimate capacity, cracking pattern and failure mode are presented and discussed. The experimental results demonstrate the efficiency of all the studied strengthening schemes in increasing the wall strength. It is concluded that ferro-cement overlay was the most efficient and also economic strengthening scheme. The failure load is almost equal to that of the unopened wall thereby compensating for the openings made in the wall. The experimental results demonstrate the efficiency of all the studied strengthening schemes in increasing the wall strength. It is concluded that ferro-cement overlay was the most efficient and also economic strengthening scheme. The failure load is almost equal to that of the unopened wall thereby compensating for the openings made in the wall.