Reverse auctions in Ariba Sourcing allow participants to submit competitive bids for goods or services in real-time. Preparation through RFIs and RFPs is important. Auctions provide price transparency and feedback to help drive savings through competition. However, auctions are not always appropriate and different strategies like RFPs may be better depending on the situation, such as when defining service levels or with few potential suppliers. Working closely with suppliers can continue to identify savings beyond initial auctions.