We have been helping our retail customers this week to prepare their businesses for their Boxing Day Sales.  We took calls yesterday on how to use the catalogue facilities in our software to manage the discounting.  We make it easy with discounting across a date range.  This can be done by product, department or category.  It can be set to end on a certain date.  Our advice went beyond traditional software support for a couple of customers.  As new retailers, they wanted advice on what to discount and the level to offer.  We were able to tell them about what we have found works in our own retail businesses.  We define rules and timelines and stick with this.  And, as I bang on here plenty of times, we measure and adjust the business accordingly.