Increasing urbanization and industrialization have exacerbated the scarcity of freshwater resources. To address this challenge, authorities worldwide are compelled to consider the treatment and reuse of wastewater generated by industries and domestic sources. To date, vermifiltration has been successfully applied for treating domestic wastewater, and the limited results from industrial applications are also promising, demonstrating its potential for industrial wastewater remediation. Vermifiltration has garnered substantial academic and industrial interest in recent decades as a sustainable approach to the remediation of domestic and industrial wastewater. The chapter on vermifiltration examines the underlying mechanisms and the current status of this approach in remediating and reusing effluents from both domestic and industrial premises. Waste valorization is an essential strategy in sustainable waste management, focusing on converting waste materials into valuable products such as energy, fuels, and raw materials. Here, an attempt has been made to identify and thoroughly discuss the mechanisms involved in vermifiltration and waste valorization. This chapter examines the progress made in vermifiltration research during the previous decade, with a focus on the underlying mechanisms for pollutant removal, system performance characteristics, and the associated by-products and current technologies, challenges, and future directions in waste valorization, emphasizing its role in the circular economy. The review concludes with insights into advancing waste valorization for achieving environmental sustainability and economic viability.