Regenerative living walls offer an innovative solution for urban wastewater management and climate adaptation, particularly for the challenges posed by the inadequate sanitation infrastructure prevalent in developing countries such as Thailand, India and Cambodia. The absence of proper sanitation systems results in uncontrolled release of human wastes, including feces, urine, washing water, and cleansing fluids, into the environment. This not only causes environmental pollution, but also contributes to significant public health issues. In many developing countries, on-site wastewater treatment systems, such as septic tanks or modified septic tanks with aerated systems, are commonly employed as the primary treatment for urban household or building wastewater. However, primarily due to short hydraulic retention times (HRTs) and unpredictable organic loading rates (OLRs), effluents of these on-site systems usually contain high concentrations of organic compounds (e.g. chemical oxygen demand (COD)) and nutrients (e.g. nitrogen), resulting in detrimental effects on the environment. To address these challenges, a paradigm shift is essential in the design concept of sanitation systems, especially in urban contexts. Moving away from the traditional ‘end-of-pipe’ approach, there is a growing need to embrace strategies centered around ‘reuse, recycle, and resource recovery.’ In this context, novel constructed wetland systems, such as living garden walls and employing novel media, emerge as promising post-treatment solutions, demonstrating potential improvements in treatment efficiencies, cost-effectiveness, ease of maintenance, and installation footprint for densely populated urban areas.