n an era where environmental sustainability and resource scarcity are becoming increasingly critical concerns, innovative approaches to wastewater treatment and energy recovery have gained significant attention. The convergence of nanotechnology and biotechnology has paved the way for revolutionary solutions that address these challenges in unprecedented ways. This book Nanobiohybrids for Advanced Wastewater Treatment and Energy Recovery delves into the fascinating realm of nanobiohybrids (NBs), offering a comprehensive exploration of their potential to reshape the landscape of wastewater management and energy harnessing. The book is divided into four parts, where Part 1 covers key concepts of microbial synthesis, water purification and energy storage. Part 2 encompasses utility of organic, inorganic and magnetic nanoparticles (NPs) as well as electroactive bacteria that constitute NBs. Further parts 3 and 4 deal with, respectively, environmental remediation and wastewater treatment using NBs. Nanobiohybrid (NB) system design amalgamates the finest characteristics of biological systems with synthetic materials. This integration encompasses the spectrum of biosystems, ranging from individual biomacromolecules (such as enzymes) to intricate biological entities (such as living cells and plants) (Liang & Liang, 2023). The synergy of biosystems and synthetic materials significantly impacts the ultimate functionality of NBs. Until now, these NBs have been created and utilized across diverse applications, including biocatalysis (Liu et al., 2019; Shen et al., 2022).The journey into the world of NBs begins with a journey through the fundamental principles of nanotechnology and biotechnology. As we embark on this exploration, we will uncover the intricacies of nanomaterials and their novel applications in wastewater treatment. From NPs that act as efficient adsorbents to nanocomposites that catalyze degradation processes, these innovations have the potential to revolutionize pollutant removal (Manikandan et al., 2022). But the realm of NBs does not stop at wastewater treatment. It also dives into the realm of energy recovery, a crucial element of sustainability (Nasrollahzadeh et al., 2021). The principles of biophotovoltaics, microbial fuel cells, and enzyme-assisted systems will come to life as we explore how these innovations bridge the gap between waste and energy. The integration of NBs into real-world applications presents both challenges and opportunities (Andriukonis et al., 2021; Teodor et al., 2020).This book is the result of collaborative efforts by experts from diverse fields, including nanotechnology, biotechnology, environmental science, and engineering. Their collective expertise shines through as they present the latest research findings, case studies, and practical insights that highlight the promise of NBs for advanced wastewater treatment and energy recovery. As you turn the pages of ‘Nanobiohybrids for Advanced Wastewater Treatment and Energy Recovery,’ prepare to embark on a journey that explores the fusion of tiny particles and living organisms – a journey that has the potential to redefine the boundaries of what is achievable in environmental stewardship. This book serves as a guide to understanding the transformative impact of NBs inviting readers to join the endeavor to build a cleaner, more sustainable future.