The demand for a more sustainable agriculture, coupled with the need for optimized crop productivity, has driven the use of microorganisms for the biocontrol of diseases and pests, as well as for growth promotion. The use of plant growth-promoting rhizobacteria (PGPR) and plant growth-promoting fungi (PGPF) in Brazilian production systems has become increasingly common, with the number of microbial inoculant registrations in the country growing every year. PGPR and PGPF occupy various niches in the rhizosphere, playing a crucial role in soil nutrient cycling, as well as influencing various plant physiological processes. In this review, we address the main mechanisms used by these microbial agents in growth promotion and the use of strain co-inoculation as a strategy to enhance the efficacy of these products. Subsequently, we conduct an analysis of the available inoculants in Brazil, detailing the microorganisms available for the main Brazilian crops, and the prospects of this market regarding research and development of new products for the coming years based on the current challenges faced.