Water scarcity is a defining challenge in semi-arid regions, where erratic rainfall, high evaporation, and increasing agricultural demands threaten food security and rural livelihoods. Sustainable irrigation in these areas depends on effective water conservation techniques that maximize water use efficiency and protect limited resources. This article reviews traditional and modern water conservation methods—such as drip irrigation, mulching, rainwater harvesting, deficit irrigation, and community involvement—tailored for semi-arid agriculture. It synthesizes recent research, case studies, and technological advances, highlighting their effectiveness, limitations, and the need for integrated, participatory approaches to ensure long-term sustainability.