Several drying processes have been investigated and reported on. These include microwave, infra-red and air-knife continuous systems and a cheap discontinuous (batch) system based on the heat-pump principle. The microwave dryer appears to be ideal for Periloc (for which it was designed) but might limit production of heavy count yarns. The heat-pump dryer is by far the cheapest installation and, when suitably modified, may compete with continuous systems in respect to volume production and costs.