Poultry processing generates strong wastewaters with characteristics that may be tailored by appropriate adjustment of the operation. The organic content has a residual fraction in the order of 200-400 mgl(-1), depending on the strength of the wastewater. The values of kinetic and stoichiometric constants related to biological treatability are observed to be quite comparable with domestic sewage. The hydrolysis of slowly biodegradable organics is best described by dual-hydrolysis kinetics with appreciably different rare constants for soluble and particulate components. The experimental results of the study may be used to evaluate the achievable compliance with existing effluent limitations and to define the optimum in-plant operation and wastewater treatment and disposal strategy. (C) 1999 IAWQ Published by Elsevier Science. All lights reserved.