Although retailers assume a position of risk on a wide variety of products, their position on any one product is not deep. Risk is spread across more than 30000 stock keeping units in a typical supermarket. A mass retailer offering general merchandise and food often exceeds 50000 skus. faced with this width of inventory, retailers attempt to reduce risk by pressing manufacturers and wholesalers to assume greater and greater inventory responsibility. Pushing inventory back up the channel has resulted in retailer demand for fast delivery of mixed-product shipments from wholesalers and manufacturers. Specialty retailers, in contrast to mass merchandisers, normally experience less width of inventory risk as a result of handing narrower assortments.However, they must assume greater risk with respect to depth and duration of inventory holding.