This study investigated the feasibi1ity of improving waste stabilization ponds (WSP) performance through the addition of attached-growth media in the pond water. An artificial media consisting of fine strings of polyvinylidene chloride was employed as an attached-growth media in the laboratory-scale and pilot-scale experiments. Better removal of organic, nutrient and suspended solids were obtained in the attached-growth waste stabilization ponds (AGWSP). The AGWSP were found to be rather stable against increased hydraulic loadings. However, the fecal coliform die-off in the AGWSP units were not significantly different from those of the control units without attached-growth media.