Abstract: A method and system is provided for triggering an advertisement for display via a computer network. One of a several part numbers is received from a user request. An advertisement to be displayed is triggered if (i) the user is associated with a pre-determined desired group corresponding to the triggered advertisement, and (ii) the user is not associated with a pre-determined no-show group corresponding to the triggered advertisement; and (iii) at least one of the received part numbers is included in the portion of part numbers. The triggering step further includes determining whether the triggered advertisement has exceeded a pre-determined maximum number of showings. An advertiser associated with the advertisement is notified of the triggered advertisement and the user. Further, responsive to the user request, stored information is searched for a part corresponding to at least one part number. Further, the user is classified by type within a vertical industry such as the airline industry.