Plant growth-promoting rhizobacteria (PGPR) have an important role in maintaining sustainable agricultural practices. Increased demand for crop production using minimal chemical fertilisers has become a great challenge for both researchers and farmers. This chapter focuses on the important classification of PGPR and their various commercial uses in promoting sustainable agricultural practices. PGPR are subdivided into three categories: plant growth-promoting bacteria (PGPB), biocontrol PGPB, and plant stress homeo-regulating bacteria (PSHB). PGPR produce secondary metabolites having biofertiliser activity such as the ability to fix nitrogen, phosphate solubilisation, potash mobilisation, and biocontrol of plants. There are various reports on using PGPR strains, Pseudomonas sp., and Bacillus sp. as biocontrol agents. Hence, this article focuses on summarising the PGPR as biofertiliser for agricultural sustainability. © Springer Nature Singapore Pte Ltd. 2019.