NATAE Practice abstract n. 11: Efficiency. Working Package 7. A NATAE practice abstract is a summary that describes an agroecological practice that can be used as a valuable resource by farmers, researchers, policy makers, and other stakeholders interested in adopting or promoting agricultural practices that contribute to sustainability, productivity, and competitiveness in the agricultural sector. This document explores water resource management in oasis systems in North Africa, emphasizing sustainable practices to optimize irrigation and preserve scarce water resources. Key strategies include localized irrigation, soil moisture sensors, rainwater harvesting, and drought-resistant crops to reduce water waste and improve efficiency. Ancestral techniques, such as multi-layered cultivation and underground water transport (e.g., Khettaras), help create microclimates and minimize evaporation. Challenges include the need for collective governance, equitable water access, and mitigating soil salinity. The goal is to ensure long-term sustainability while adapting to climate change and water scarcity.