Many middle- and low-income countries are experiencing rapid urbanization, which creates a need for services, including sanitation. While some areas in some towns and cities are sewered, most people, especially the urban poor, continue to use various forms of on-site sanitation. These require periodic emptying and the material removed from them must be treated before reuse or discharge to the environment. Faecal Sludge and Septage Treatment confronts the urgent need to treat increasing volumes of faecal sludge and septage in the rapidly expanding towns and cities of the global south. It discusses the urban contexts that influence treatment requirements and overall septage treatment processes. It examines the options and design approaches at each stage of treatment, from reception, through preliminary treatment, solids – liquid separation, anaerobic and aerobic treatment of the separated liquid and solid fractions to systems to render treated products suitable for reuse in either agriculture or as a fuel. Faecal Sludge and Septage Treatment provides straightforward guidance on the options for faecal sludge treatment and the choices between those options. All concepts and approaches are clearly explained so as to make Faecal Sludge and Septage Treatment accessible to a non-specialist readership. Faecal Sludge and Septage Treatment is essential reading for planners and engineers working in local government; specialist central government departments; NGOs and consulting firms working on the planning and design of septage treatment plants; researchers and students studying urban sanitation.