The unpredictable nature, biosynthetic capabilities and inimitableness of microorganisms give a specific set of environmental conditions to crop/plant for their sustainable growth. It has prepared microbes as interesting candidates for solving various problems in the field of agriculture. Microorganisms have been used in a variety of ways since long ago for human and animal health, genetic engineering, medical technology, food processing/safety/quality, and could be used in a more effective manner in the growth of agriculture and environmental protection (Jez et al. 2016). Microbial technologies have been used to diverse agricultural/environmental problems with considerable success in the recent past, but they have not been fully investigated. It is difficult to constantly replicate the beneficial effects of microbes. Microorganisms are effectual only when they are presented with optimum and suitable conditions for metabolizing their substrates including the available water, oxygen, temperature and pH of their developing environment. Various types of inoculums of different microbial cultures are available on the market and their use has been rapidly increased in agriculture. Since microorganisms are useful for the elimination of problems associated with the use of pesticides, fertilizers and chemicals, they are now widely used in organic agriculture and nature farming (Aktar et al. 2009). Environmental pollution, caused by extreme use of chemical fertilizers/pesticides in the soil, transport of sediment/groundwater and unnecessary soil erosion has caused serious environmental and social problems worldwide. Often researchers have attempted to solve these problems using established chemical and physical methods. However, they felt that such 66problems cannot be solved without using microbial methods. For many years, microbial ecologists and soil microbiologists have been inclined to differentiate soil microorganisms as beneficial/harmful according to their functions and how they affect plant growth, yield and soil quality. Advantageous microorganisms for agriculture are those that can detoxify pesticides, fix atmospheric nitrogen, enhance nutrient cycling, decompose organic wastes/residues, suppress plant diseases/soilborne pathogens, and produce bioactive compounds (hormones, vitamins and enzymes that stimulate the growth of the plant) (Nayak et al. 2018). This chapter explains the current scenario in agriculture, improving agriculture with microbes, controlling soil microbes for optimum crop production, functions of microorganisms in agriculture, and the application of beneficial microbes in the imperishable growth of agriculture.