Preface.1. Microbial Community Analysis.Observation and model analysis for the bacterial community structure of activated sludge (T. Matsuo, F. Kurisu).Stability, persistence and resilience in anaerobic reactors: a community unveiled (J. Tiedje, A. Fernandez, S. Hashsham, S. Dollhopf, F. Dazzo, R. Hickey, C. Criddle). Strategic approach for characterization of bacterial community in enhanced biological phosphate removal (EBPR) process (T. Mino, H. Satoh, M. Onuki, T. Akiyama, T. Nomura, T. Matsuo).Microbial community structure and their activity in aquatic environment (M. Nasu, N. Yamaguchi, K. Tani). Analysis of complex microbial community in soil and wastewater treatment processes by cloning method (H. Oyaizu, H. Kim, D. Honda, I. Takahashi, S. Suzuki, H. Satoh, T. Mino). Microbial community analysis of thermophilic contact oxidation process by using PCR-DGGE method (F. Kurisu, H. Satoh, T. Mino, T. Matsuo). Relating function and community structure of complex microbial systems using neural networks (S.A. Hashsham, T.L. Marsh, S.L. Dollhopf, A.S. Fernandez, F.B. Dazzo, R.F. Hickey, C.S. Criddle, J.M. Tiedje). Comparison of microbial communities in anaerobic granulated sludge reactors treating benzoate, methyl benzoate and terephthalate (W.-T. Liu, J.-H. Wu, O.-C. Chan, S.-S. Cheng, I.-C. Tseng, H.H. P. Fang). 2. Health-Related Microorganisms. Quantitative risk assessment of Cryptosporidium in a watershed (S. Ohgaki, Y. Masago, H. Katayama, T. Hirata, A. Hashimoto, M.Z.B. Alam).PCR determination of inactivated RNA coliphage Q&bgr; (H. Katayama, M. Nakamura, S. Ohgaki).Evaluation of UV-radiation and its residual effect for algal growth control (M.Z.B. Alam, S. Ohgaki). Bacteriophages, coliform and fecal coliform bacteria in wastewater in southern Thailand (P. Claydong, S. Danteravanich, C. Siriwong, S. Uakritdathikarn). Assessment of treatment efficiency by quantitative recovery of indicator bacteria and pathogens in sewage effluents (I. Khan, N. Kamal). 3. Biological Nutrient Removal.Visualization of microscale distribution of nitrifying bacteria in biofilms formed in various type wastewater treatment processes (Y. Aoi, T. Miyoshi, T. Okamoto, S. Tsuneda, A. Kitayama, E. Kayano, T. Nagamune, A. Hirata).Nitrous oxide production in nitrogen removal process treating domestic sewage from combined sewer system (K. Hanaki, T. Nakamura, T. Matsuo). Quinone profile analysis of activated sludge in enhanced biological P removal SBR treating actual sewage (H. Furumai, M. Fujita, F. Nakajima). Applicability of FISH, dot blot hybridization, antibody immobilized latex coagulation, and MPN techniques as enumeration methods for ammonia-oxidizing bacteria in various water environments (S. Konuma, H. Satoh, T. Mino, T. Matsuo). Nitrous oxide and nitric oxide emissions during sulfur denitrification in soil-water system (K. Hasegawa, K. Hanaki). FISHing for biomass in activated sludge mixed liquor: the slippery VSS fraction (D.D. Mudaly, B.W. Atkinson, F. Bux). Identification of predominant microbial populations in a non-phosphate removing anaerobic aerobic bioreactor fed with fermented products (S.-J. You, W.-T. Liu, M. Onuki, T. Mino, H. Satoh, T. Matsuo, C.-F. Ouyang). Microbial aspects of autotrophic denitrification of wastewaters (A. Koenig, L.H. Liu). 4. Sludge Reduction and Material Recovery.Membrane bioreacter: an advanced wastewater treatment/reclamation technology and its function in excess-sludge minimization (K. Yamamoto). Poly-&bgr;-hydroxyalkanoate metabolism in activated sludge (M.C.M. van Loosdrecht, J.J. Beun, J.J. Heijnen). Synthesis of biopolyesters by microorganisms in activated sludge (H. Satoh, H. Takabatake, T. Mino, T. Matsuo). Material recovery from wastewater using photosynthetic bacteria (F. Nakajima, K. Izu, K. Yamamoto). 5. Water and Wastewater Treatment in Asia, Tropical and Subtropical Regions.Microbial ecology controls the establishment of fecal bacteria in tropical soil environment (R.S. Fujioka, M.N. Byappanahalli). Anaerobic wastewater treatment in (sub-)tropical regions (H.H.P. Fang, Y. Liu). Optimization of enhanced biological wastewater treatment processes using a step-feed approach (C.-F. Ouyang, Y.-J. Chou, T.-Y. Pai, H.-Y. Chang, W.-T. Liu). Upgrading of waste stabilization pond to baffled reactor for domestic wastewater treatment (Z. Ujang, S. Yaacob, M.A. Kassim). Potentials of vertical-flow constructed wetlands for septage treatment in tropical regions (T. Koottatep, C. Polprasert, N.T.K. Oanh, U. Heinss, A. Montangero, M. Strauss).