Results are described from field trials on the application of a new type of filter, the Howden-Wakeman fibre bed filter, to the treatment of distillery effluents and municipal wastewaters. The filter showed substantial reductions in suspended solids, E. coli, BOD and COD, for the waste streams evaluated. Oxidation of nitrogen was also found in the sewage treatment applications. The filter design was proven to be adaptable so as to be easily and rapidly set up on each new test site, and was found to be reliable in use.