Centridry® is a biosolids drying process developed by Humboldt-Decanter of Germany. The process uniquely combines centrifuge dewatering with flash air drying to produce a solids product with 50 to 60 percent solids, and drier. A five-month demonstration project was recently completed at King County’s East Section Reclamation Plant (ESRP) in Renton to evaluate the technology for possible implementation at the West Point Treatment Plant (West Point) and/or ESRP. This paper describes the Centridry process, the potential benefits to King County, King County’s approach for evaluating the technology, design and start-up of a 4.5 dry metric ton per day (five dry ton per day; 5-TPD) demonstration plant, and operating results.