This book explores the areas of microbial ecology and agricultural biotechnology brought about by third-generation sequencing technologies and multi-omics platforms. It focuses on the sequencing of plant growth-promoting rhizobacteria (PGPR) genomes, metagenomic studies of the rhizosphere and metabolomics profiling of bioactive secondary metabolites, all of which have enabled the development of rhizomicrobiome engineering as a powerful tool for enhancing crop productivity and resilience. The chapters cover topics such as the development of climate-smart bioinocula, the role of host genotype in microbial inoculant efficacy, and the integration of omics data in strain selection. The book critically assesses the challenges and successes in developing microbial solutions that confer tolerance to biotic and abiotic stresses. Concepts such as biodegradable inorganic biostimulants and synthetic biology applications are explored, offering a perspective on modernizing traditional biofertilizer design strategies. Through comparative analysis, the book rationalizes investment and guides policy by highlighting the advantages of contemporary microbial tools over conventional methods.This volume is part of the book series Microorganisms for Sustainability and serves as a vital resource for scientists, industry stakeholders, and policymakers involved in rhizosphere microbiology, PGPR biology and microbial biotechnology. It helps the researchers, academics, and professionals in the field to understand the latest advancements and their practical implications in agricultural biotechnology.