A dynamic vertical network management system is adapted to broker, between each publisher of a group of publishers and each advertiser of a group of advertisers, the sale of at least a portion of the each publisher's inventory of advertisement impressions. At least a portion of the advertisers are clients of a dynamic vertical network operator (DVN) with the DVN purchasing inventory from the publisher and utilizing such purchased inventory to fulfill advertising orders placed by the client with the DVN (network orders). A publisher data store stores, for each publisher of the group of publishers, a group of segmented ad placements. Each segmented ad placement comprises: i) a placement ID identifying an advertisement placement region within a web page; and ii) at least one distinguishing traffic attribute parameter. An advertisement-order data store stores, for each segmented ad placement, a group of advertisement orders. Upon receiving an ad request from an end user system rendering the web page, an order delivery system: i) determines the selected ad placement, ii) determines an open order for the selected ad placement meeting selection criteria, and iii) if such order is a DVN order: a) determines a client network order meeting network order criteria, and b) delivers ad content associate with the selected network order.