This study examines seven commemial enzymes with cellulase activity xylanase activity or a combination of both applied to paper stock in the pulper at optimum conditions for each enzyme. Results of deinking efficiencyshowed that most enzyme preparations performed better than the conventional chemical method. Pilot results agreed with laboratory experiments for two enzymes. Dewatering and dispersion steps and subsequent reflotation and washing may therefore not be essential Their elimination could save capital costs and reduce electrical energy consumption.