The success of digital printing in the office and the home is a matter of historical fact. Facsimile machines, personal printers, office and networked printers are the mainstay in the hard copy output of document . Newmultifunction digital output devices which combine the functions of copying, printing, faxing and collation will soon become prevalent. At the high end, electrophotography, now a sixty-year old technology, still reigns supreme. Now that cartridges allow the replacement of the major components of the process, the word "reliable" is finally being associated with electrophotography! Cartridges also facilitate a captive, ongoing, consumable business, vital to the profitability of manufacturers of hardware.