Abstract: An extracorporeal blood processing method includes a set-up phase establishing certain conditions in blood being processed prior to separation of the blood into components. Also, a blood processing method contemporaneously extracts selected multiple blood components from a blood processing vessel. Blood is separated into components in the blood processing vessel in a centrifugal field. Further, an extracorporeal blood processing method establishes a packing factor in the blood processing vessel prior to collecting red blood cells.