An individually targeted content delivery system and methods which allows content to be delivered to at least one set top box while preserving the privacy of the set top box users. The system and methods of the present invention determine one or more user models for a set top box based on user interactions with the set top box and content to be displayed on the set top box is selected based on the user model. The present invention also allows a set top box to determine when content has been experienced by a set top box user, and to require a set top box user to experience at least one pre-defined content before other content can be viewed.