Extreme climatic phenomena such as drought, salinity, and water scarcity will likely impact the global living conditions. These problems are particularly noticeable in arid and semi-arid regions that cover the majority of the Earth's land surface. Lack of water is one of the most crucial restraints on crop production in the Mediterranean Region. The shortage of freshwater resources, their uneven distribution, irregular rainfall, and climate change have significantly impacted sustainable agriculture in these regions. Therefore, efficient water management and cultivating drought- and salt-tolerant crops such as quinoa and amaranth seem essential for sustainable crop production in water-scarce regions. Cultivating new crops under harsh conditions is one of the approaches often used to preserve agricultural output in such locations for food security. This chapter's purpose is to provide information on how to enhance agricultural crop production in arid and semi-arid areas that are subject to a variety of abiotic (water, salt and heat) conditions. For this, agricultural water management strategies under water scarcity was discussed. Correspondingly, this research evaluated quinoa yield and water productivity responses to regulated deficit irrigation, partial root zone drying, conventional deficit irrigation, and full irrigation utilizing above and below-ground drip systems. This research has shown that deficit irrigation was very beneficial at different trial sites. The results suggest that quinoa responds positively to full saline and freshwater irrigation compared to deficit irrigation. Ultimately, considering its stress tolerance, adaptation to a variety of agricultural circumstances, multiple cultivars that can be cultivated from sea level to highlands, nutritional component, and economic importance, quinoa can be recommended as an alternative crop for marginal agricultural areas. This chapter also examines the challenges of introducing quinoa in this region, the recent condition and prospects of crop dissemination in Türkiye, applications and markets, and dissemination concerns and problems.