In this study, the performance of an anaerobic baffled reactor (ABR) in the treatment of domestic wastewater was assessed by extrapolating existing understanding of the characteristics of laboratory-scale ABRs to design a pilot-scale reactor. The pilot-scale reactor was operated and analysed at Umbilo and Kingsburgh wastewater treatment plants (WWTP) where it was fed municipal wastewater. A parallel study investigated water use and wastewater generation patterns in a peri-urban community. A modelling study was undertaken using data from the pilot-scale ABR from different operating periods and measured community wastewater characteristics, and used to predict effluent characteristics of an ABR treating domestic wastewater from a dense peri-urban area under specified operating conditions. The cumulative experiences and information gained in all the parts of this project were brought together to propose improvements in ABR dimensions and installation in Guidelines for the design, operation and maintenance of an ABR treating domestic wastewater. Recommendations regarding the appropriateness of the system for different applications and suggestions for management and maintenance strategies were made.