Enhancing and maintaining soil biological functions is essential for the productivity and sustainability of agricultural systems, particularly in sandy soils, which are often low in biologically available organic carbon, the primary energy source required for soil microbial activity. Given their low soil fertility, microbial communities drive many vital soil processes that support productive grain production systems. The lower clay content in sandy soils makes microbes associated with roots and decomposing residues are essential for aggregate formation and soil structure. This presentation summarizes over two decades of research on soil and crop management in sandy soils across southern and Western Australian agricultural regions. Most microbial populations in sandy soils (average >60%) are concentrated near roots and decomposing crop residues. Therefore, depletion of carbon-rich microsites and changes to quality of C inputs can affect the distribution, diversity and metabolic status of microbial communities impacting overall biological resilience. For example, the boom-bust cycle in C supply under fallow-crop and low intensity cropping systems generally reduces resilience in microbial biomass, catabolic potential and specific functional groups involved in N, P and S cycling and microbiome diversity. As carbon and biota in sands are relatively unprotected, these soils quickly respond to rainfall and favourable environmental conditions resulting in rapid C and nutrient turnover and quick release of plant available nutrients. Adopting a high input, intensive cropping regime on sands can increase nitrogen mineralisation (>50%) and reduce leaching (>60%). Long term (5-7 years) adoption of stubble retention and conservation agricultural practices has been shown to improve soil microbial and faunal activity, alter microbial diversity and network structure and improve biological disease suppression, removing disease constraints to crop production. Overall, understanding the limits and potential to improve microbiota resistance and resilience to stresses remains a priority for research to better harness biological functional capacity in sandy soils.