Interaction, whether mutualistic, symbiotic or suppressive, that coexists in soil ecosystem within the plants, microbes or microfauna, is the most important phenomenon which regulates the soil health vis-à-vis the plant health. The most intense interaction between microbes and plants takes place at the rhizosphere, where complex biological and biochemical activities between microbes-microbes, microbes-plants and plants-plants are always going on to influence the biodiversity of beneficial organisms, suppression of pathogenic microflora and physico-chemical behaviour of soil. Microorganisms appear to be excellent indicators of soil health as they respond quickly to changes in soil eco-system and have intimate relations with their surroundings owing to their high surface to volume ratio. The useful microorganisms can be exploited for the improvement of soil health since they are involved in many soil processes.