A new biological phosphorous and nitrogen removal process is developed. The process is based on biofilm on carrier elements with enhanced biological phosphorous removal and simultaneous nitrification and denitrification in a continuous process. Results from 3 years of pilot and laboratory experiments are presented with regards to removal of organic substances, phosphorous and nitrogen. This process demonstrates essential benefits and improved performance compared to other EBPR-processes in operation today. The first full scale plant was put in operation in May 2016 at Hias WWTP in Norway.