Dr. Haider M. Zwain is an Associate Professor in Water and Wastewater Treatment, and Deputy Dean for Scientific Affairs at the College of Water Resources Engineering, Al-Qasim Green University. Dr. Haider M. Zwain has obtained his PhD at Universiti Sains Malaysia, and worked jointly with the Institute of Environmental Engineering, National Chiao Tung University, Taiwan, and Nanyang Environmental and Water Resources Institute, Nanyang Technological University, Singapore. His research interests are: Water and Wastewater Treatment, Environmental Engineering, Water Resources Management, Biological Process, Biological Modeling, and Anaerobic Digestion.