Monitoring subscriber viewing interactions, such as television viewing interactions, and generating viewing characteristics therefrom. Generating at least one type of subscriber profile from at least some subset of subscriber characteristics including viewing,
purchasing, transactions, statistical, deterministic, and demographic. The subscriber characteristics may be generated, gathered from at least one source, or a combination thereof. Forming groups of subscribers by correlating at least one type of subscriber profile. The subscriber groups may correlate to elements of a
content delivery system (such as head-ends, nodes, branches, or set top boxes (STBs) within a cable TV
system). Correlating ad profiles to subscriber / subscriber group profiles and selecting targeted advertisements for the subscribers / subscriber groups based on the correlation. Inserting the targeted ads in place of default ads in program streams somewhere within the
content delivery system (head-end, node, or STB). Presenting the targeted ads to the subscriber / subscriber group via a television.