A file with code for displaying an electronic page containing an embedded content-tag is downloaded at a user display station. The page contains space for displaying selected content. A first request to a content delivery network for information associated with the embedded content-tag and processing code is issued in response to receipt of the embedded content-tag at the user display station. Information associated with the embedded content-tag and the processing code is downloaded to the user display station from the content delivery network in response to receipt by the content delivery network of the first request. The information associated with the embedded content-tag includes information about a plurality of active content campaigns associated with the embedded content-tag and targeting criteria. One of the plurality of active content campaigns is selected at the user display station using the processing code and in accordance with the information about the active content campaigns and the targeting criteria.