A demand-side platform (DSP) is a system that allows digital advertisers to manage multiple ad exchange and data exchange accounts through one interface. Real time bidding for displaying online ads takes place within the ad exchanges, and by utilizing a DSP, marketers can manage their bids for the banners and the pricing for the data that they are layering on to target their audiences. Much like Paid Search, using DSPs allow users to optimize based on set Key Performance Indicators such as Cost-per-clicks, and Cost-per-action.