Water scarcity and environmental pollution are the major global concerns that require innovative solutions to circumvent the challenges associated with conventional wastewater treatment (WWT) methods. One promising approach involves integrating biological processes, such as activated sludge systems and microbial fuel cells, with cutting-edge nanotechnological interventions. This combination offers potential improvements in the efficiency and sustainability of wastewater treatment processes. The chapter overviews the current state of wastewater treatment, alongside the limitations of prevailing technologies. The principles and mechanisms supporting advanced biological processes and their ability to influence microorganisms’ inherent competencies to degrade various pollutants are explored. In addition, nanotechnological applications in wastewater treatment, accentuating nanomaterials’ exceptional properties that improve catalysis, adsorption, and separation processes, are accounted. A synergistic effect of nanotechnology and advanced biological processes that address problems like microbial resistance, emerging contaminants, and enhance treatment efficiency are also briefly discussed. Transformative potential of combinatorial approaches for sustainable achievement of wastewater treatment is comprehensively discussed. This underscores the inevitability of ongoing research and technological invention to augment this integration and plan the field for resource-efficient and an eco-friendlier future.