As was mentioned in the previous reply; most parallel scanners have a parallel bypass port built into the back of them. If you do not have the bypass built into the scanner you can use a parallel switch, more commonly used to connect two printers to a single parallel port. <A class=ftalternatingbarlinklarge target=blank href="http://catalog.belkin.com/IWCatProductPage.process?Merchant_Id=&Section_Id=1586&pcount=&Product_Id=13095&Section.Section_Path=%2FRoot%2FPeripheralSharing%2FReversibleSwitches%2Fct_Id>">Belkin</A> makes a manual model and also an automatic model that supposedly senses which unit is being addressed. I use one of the "manual" models for my two printers. All I do is to call up the software program that switches the switch from my desktop and the unit is ready to use.