Nature-based solutions (NbS) for decentralized wastewater treatment are gaining recognition due to their sustainability, cost-effectiveness, and environmental benefits. These solutions, such as constructed wetlands, waste stabilization ponds, soak pits, and hybrid aerobic/anaerobic systems, offer an alternative to traditional, centralized wastewater treatment, particularly in rural, peri-urban, and resource-limited areas. This chapter discusses the types of NbS for wastewater treatment, the challenges encountered in their implementation, and offers suggestions for improvement, such as incorporating smart technologies, promoting hybrid systems, and enhancing public engagement. It also explores future prospects, including the integration of resource recovery, resilience to climate change, and the growing role of NbS in addressing global water and sanitation issues. By addressing these challenges and capitalizing on emerging trends, NbS can play a central role in sustainable wastewater management.