**Abstract**

Phosphorus (P) is one of the macronutrients required for the optimum growth and development of plants. The deficiency of P can be compensated by adding chemical fertilisers, which are expensive and have a negative impact on the ecosystem. Solubilisation of phosphate by microorganisms is an emerging application for ecofriendly and sustainable agriculture practices. This chapter discuss the importance of P for plants, the main problems related to the over-exploitation of natural reserves of P and chemical fertilisers, the diversity of phosphate-solubilising microorganisms (PSM), the ability of microorganisms to solubilise phosphates and key mechanisms of microbial P solubilisation, the capability of microorganisms to formulate phosphaterelated nanoparticles, the potential of PSM to develop as commercial level biofertiliser and contribution of PSM for achieving Sustainable Development Goals (SDGs). This chapter will highlight the input of PSM in sustainable agriculture.

**Keywords:** phosphate, Solubilisation, microorganisms, plant, soil
