A comprehensive review of the roles played by the airflow, wetting and spin finish on the air-jet texturing, process is given. The results of an experimental investigation of the air-jet texturing process using residual spin finish, yarn-to-yarn static and kinetic friction, filament strength, filament diameter, and on-line tension measurements and high-speed cine-photography are reported. Filament yarn motion in different regions of the texturing nozzle during dry and wet texturing was analyzed. During the study it was found that water acted as lubricant to reduce friction between the filaments in the wet texturing process as the filament yarn traveled through the nozzle enabling easier relative motion of the filaments resulting in enhanced entanglement. Wet texturing also reduced spin finish on the yarn surface, which in turn, caused an increase in static friction between the filaments of the textured yarn resulting in better fixing of the loops and consequently superior yarns.