A method of delivering advertising in an online environment includes determining an intent of a user interacting with an e-commerce website and determining a hurdle rate, based at least on the intent of the user, that identifies a threshold amount to be bid by an advertiser in order to display an advertisement to the user interacting with the e-commerce website. The method may further include selecting, from a plurality of advertisements, one or more optimal advertisements having a combined advertiser bid that exceeds the determined hurdle rate. The method may further include providing one or more controls in a user interface of a client computer system, each of the controls being associated with a respective advertisement of the one or more optimal advertisements and adapted to enable the user to select one or more of the controls, and providing an element, responsive to an input of the user, that is adapted to display, to the user, the respective advertisements selected by the user.