<p>Microbial communities in arid soils are frequently subjected to extreme drought and salinity, resulting in significant changes to their structure, diversity, and ecological function. This review focuses on the unique physiological and molecular approaches allowing microbes to maintain resilience under abiotic stresses, such as osmotic adjustment via accumulation of compatible solutes, biofilm development, antioxidant defense strategies, and regulation of stress genes. The function of rhizosphere-associated microbes, especially plant growth-promoting rhizobacteria and arbuscular mycorrhizal fungi, is outlined regarding the promotion of plant–microbe interactions and soil stability. In addition, we discuss novel applications of microbial inoculants, secondary metabolites, and nano-biotechnological tools for enhancing soil health and crop productivity in drought- and salt-stressed areas. Understanding these adaptive mechanisms is essential for the design of microbial-based strategies to maintain agriculture and ecosystem functioning in arid landscapes.</p>