Electronic communications network linking the trading floors of seven registered exchanges to permit trading among them in stocks listed on either the NYSE or AMEX and one or more regional exchanges. Through ITS, any broker or market maker on the floor of any participating exchange can reach other participants for an execution whenever the nationwide quote shows a better price available. A floor broker on the exchange can enter an ITS order to assure excecution of all of an offering or bid, instead of splitting it with competing brokers.