Water remains a critical resource for sustained well being of its citizens. Sustainable development, of which reuse of wastewater is an essential part, permits a balanced management of water resources while contributing to the maintenance of quality standards. To reuse wastewater and maintain the quality of water bodies, wastewater must be treated before discharge. MBRs are ready to maintain water sustainability with small footprints.Introduction of media into MBR, not only further reduces footprints but also supports denitrifying bacteria and as a result the total nitrogen removal can be enhanced. This book provides a complete insight into the attached growth MBR (AG-MBR) using sponge as media. AG-MBR setup, materials used, methodology adopted and results are discussed in this book.