Proposals to further lower particulate matter standards for heavy duty diesel powered vehicles throughout the world, have prompted further interest in particulate filter based aftertreatment solutions. Continuously regenerating traps have been utilised in Europe as a retrofit technology for more than 6 years and this study summarises that experience. Predominantly the growth in the market for the continuously regenerating trap has been in those countries which have promoted the use of ultra-low sulfur diesel fuel (i.e. less than 50 ppm S) - Sweden, Germany, and the UK, and to a lesser extent in another seven countries.A selection of continuously regenerating traps was taken from the field after high road mileage accumulation, up to 600,000 km, and subsequently tested for performance on diesel engine bench dynamometers; the results of these studies are reported and discussed. The continuously regenerating diesel particulate filter system described in this paper has shown itself to be very robust and to date has required no additional regeneration support or input controls on the applications in the field. It is anticipated that the continuously regenerating technology will be applied to many more diesel engines as the availability of very low sulfur diesel fuels becomes more widespread.