The treatment of textile waste water is commonly carried out using biological (mainly aerobic) and physico-chemical systems. However, anaerobic bioreactors can be used to at least partially treat these effluents and provide a number of significant advantages. The most attractive feature for the treatment of textile effluents is the decolourisation of many dyes under the reducing conditions present in an anaerobic reactor. Laboratory-scale results on this particular topic are here reviewed. A second major advantage of anaerobic processing is its ability to treat wastestreams with high organic loads such as the effluents from the desizing and scouring operations currently employed in the textile manufacturing industry. Reports on successful, full-scale and pilot-scale plants are also reviewed and some limitations are discussed. © 1998 Society of Chemical Industry