A directed order process and related market center are disclosed, wherein a market center grants permission to order sending firms to send directed order flow to participating designated market makers. Such designated market makers create a virtual guarantee order book for each permissioned order sending firm. If an order sending firm sends a directed order to the market center that is marketable against a virtual guarantee order, then the market center automatically pairs the orders in a two-sided directed cross order instruction, which executes against any superior trading interest in the marketplace first before crossing.