the progress of dielectric heating at radiofrequency (rf) heating and drying technology in europe over the last 20 years is reviewed. certain established processes like plastics welding and wood glueing have advanced by improved materials handling techniques and process control. the use of rf energy to post bake cereal and sugar based products like biscuits (cookies) has become accepted both in new plant and as retrofits. the textile industry has recognized the benefits of using 'volumetric' heat transfer to dry packages of yarn and other fiber forms. both examples have prospered because of a greater understanding, by equipment manufacturers and by users, of the broader aspects of heat and mass transfer. recent developments in simultaneous application of radiofrequency and conventional convective heating in the same dryer or oven casing have resulted in a range of equipment in which the major part of the heat is supplied by fossil fuels but having improved performance due to the enhanced diffusion effected by a small proportion of radiofrequency energy (edited author abstract) 6 refs