Microbial Community Analysis surveys the vast amount of theoretical and practical knowledge on the design of biological treatment systems. It describes the different types of biological wastewater systems, the role of microbial diversity in these systems, and how this affects design and operation, methods for studying microbial community dynamics, and mathematical modelling of these systems. Contents Biological methods for the treatment of wastewaters Biodiversity and microbial interactions in the biodegradation of organic compounds Microbial population dynamics in biological wastewater treatment plants Molecular techniques for determining microbial community structures in activated sludge Principles in the modelling of biological wastewater treatment plants Practical considerations for the design of biological wastewater treatment systems Scientific and Technical Report No.5