The challenges to meet the food requirement of the burgeoning population and stabilized productivity of agriculture lands can only be met by a second green revolution. After steadily declining for over a decade hunger is on the rise again, affecting million people of the global population. Therefore, crop yields must be increased substantially over the coming decades to keep pace with global food demand. The plant rhizosphere is a multidimensional and dynamic ecological environment of complicated microbe-plant interactions for harnessing essential macro and micronutrients from a limited nutrient pool. This book will showcase naturally-occurring endophyte which can be explored for nutrient mineralization and mobilization for sustainable agriculture. This will cover recent trends, prospects, critical commentaries and advancement in the research area focusing on naturally-occurring beneficial endophytic microbes. Thus, it is proposed to bring out new scientific insights and frontiers of research that have exploration of endophyte for mineral nutrient management in soil and crops. The chapters are contributed by leading scientists across the globe. The book will be useful to agronomists, microbiologists, ecologists, plant pathologists, molecular biologists, environmentalists, policy makers, conservationists, and NGOs working for the crop production and productivity development and consequently over all agricultural significance.