Utilization of highly specific enzymes for various textile-processing applications is becoming increasingly popular because of their ability to replace harsh organic/inorganic chemicals currently used by the textile industry. Thus, a significant decrease in the amount and toxicity of textile wastewater effluents is achievable. It was established that ultrasound does not inactivate the complex structures of enzyme molecules and as a consequence there was significant improvement in the performance of both cellulase and pectinase enzymes. The experimental data indicate that the maximum benefit provided by sonication occurs at relatively low enzyme concentrations. Ultrasonic energy significantly intensified enzymatic activity on various types of cotton fabrics, but it did not contribute to a decrease in tensile strength. The combined enzyme/sonication treatment of cellulosic textiles offers significant advantages such as less consumption of expensive enzymes, shorter processing time, less fiber damage and better uniformity of treatment. Published in 2002 for SCI by John Wiley Sons, Ltd.