1. A system for implementing an agent-based application program on a computer, comprising: a processor; an input device coupled to the processor, for accepting input; an output device coupled to the processor, for providing output; memory unit coupled to the processor, for storing data and program instructions; an operating system, stored in the memory and managing a plurality of processes created by execution of program instructions in the memory unit by the processor; and at least one agency application unit coupled to the processor and managing a plurality of agents stored in the memory unit, and including: a master dispatcher coupled to the plurality of agents, for receiving from, and sending messages to the agents, and responsive to all agents being inactive, selecting an agent and activating the selected agent; the plurality of agents, each agent responsive to being activated by the master dispatcher, for executing an application function, each agent comprising: a message dispatcher for receiving a signal from the master dispatcher activating the agent, and for dispatching at least one message providing for execution of the application function; at least one message queue, for receiving and storing at least one message from the master dispatcher and from other sources, and operatively coupled to the message dispatcher and responsive to the agent being active, for passing at least one stored message to the message dispatcher for dispatching; and a message processor operatively coupled to the message dispatcher and receiving a dispatched message, for executing the application function of the received message.