A local-area-network based system for shared remote access or control of application programs in one or more computers by one or more other computers is provided having particular utility for trading rooms of securities firms, wherein each operator position is permitted the capability to access any of a number of information services. Information services, each of which communicates with a personal-computer-based video source running an applications program specific to that information service, are represented on a local-area network as nodes called servers. Each server runs the application program, unmodified, together with other terminate-and-stay-resident software which periodically broadcasts a video message, the content of which is the change of the application program display screen contents since the time of the last broadcast. The sender of the broadcast does not watch for the acknowledgements from recipients, which are other nodes on the network called clients, nor does the sender maintain a list of intended recipients. If a recipient misses a video message broadcast, it may request that the sender broadcast the contents of the entire display screen contents. Each client runs terminate-and-stay resident software which may through a hot key sequence entered from the client's keyboard request control of the application program of a particular server. Upon being granted such control, which may be shared among two or more clients, the client may send keystrokes to the server for controlling its application program.