Book excerpt: The Earth's population, currently estimated at 7.86 billion, is expected to rise to 9.8 billion by 2050. This increase will inevitably lead to a greater pressure on agricultural land in order to achieve food security. However, agricultural sustainability is still constrained by its over-reliance on chemical fertilizers, pesticides, and herbicides. These conventional practices may lead to severe negative environmental consequences, typically evidenced by a loss in soil organic matter and reduction in soil microbial diversity, negatively impacting on food production. The challenging situation identified above is likely to be worsened by climate change, soil health deterioration, and by a range of biotic and abiotic stresses. Biotic and abiotic stress management, enhancement of crop yields, nutrient cycling, and natural bio-resources harnessing optimization can be achieved by modifying the soil microbiome. Discovering and exploiting potentially beneficial soil microbes is crucial to achieving sustainable agriculture production in the face of these issues. Among the plethora of potentially beneficial microbes, plant growth-promoting microbes (PGPM) and arbuscular mycorrhizal fungi (AMF) are often considered to be safe and environment-friendly tools to deal with various stresses. The interest in adopting novel methods that increase crop yield, soil health, and fertility will be positively impacted by a better understanding of the fate and behaviour of PGPM and AMF use in agriculture.