Abstract: The system and method of the preferred embodiment supports trading of securities over the Internet both on national exchanges and outside the national exchanges. The preferred embodiment supports an improved human interface and a continuous display of real-time stock quotes on the user's computer screen. The ergonomic graphical user interface (GUI) of the preferred embodiment includes several functional benefits in comparison with existing on-line consumer trading systems. In the preferred embodiment, the users are subscribers to a securities trading service offered over the Internet. Preferably, each subscriber to this service is simultaneously connected from his own computer to a first system which provides user-to-user trading capabilities and to a second system which is a broker/dealer system of his/her choice. The system providing the user-to-user trading services preferably includes a root server and a hierarchical network of replicated servers supporting replicated databases.