This book explains microbial roles for agricultural sustainability, especially under climate changes, including the role of microorganisms in sustainable agriculture. Major coverage entails microbial enzymatic roles in agriculture, microbial phytohormones as promising sustainable plant bioagents, and phosphate-, potassium-, and calcium-solubilizing microbes as alternative biofertilizers. It introduces microbial solutions to mitigate the biotic and abiotic stress, with high attention to rising temperature and water limitation due to the climate changes. This bookPresents a summarized insight into important roles of microbes in facing the climate changes;Describes plant–microbe interaction in sustainability;Highlights roles of microorganisms in limited agriculture water sources;Provides an insight into microbial phytohormones as promising plant-sustainable bioagents;provides comprehensive overviews of microbial bioremediation roles for soil reclamation. This book is aimed at researchers and graduate students in microbiology, agriculture, and sustainability.