1. A plant diagnostic system for diagnosing a problem with a plant, the plant having a plurality of subsystems, each of the plurality of subsystems having one or more components that participate in the operation of the plant by performing one or more plant operations, each of the plurality of subsystems also having one or more sensors that detect the one or more plant operations and transmit data related thereto, said system comprising: an agent-based plant diagnostic network having an adaptive global agent located in a central facility, a plant expert agent located at the plant and a plurality of subsystem resident agents, each of said plurality of subsystem resident agents assigned to one of the plurality of subsystems of the plant; and a diagnosis agent operable to be instructed by said adaptive global agent, transmitted to said plant expert agent, received by said plant expert agent, transmitted by said plant expert agent and received by said adaptive global agent; said plant expert agent operable to receive said diagnosis agent transmitted from said adaptive global agent, transmit an instruction from said diagnosis agent to at least one of said plurality of subsystem resident agents, receive information from said at least one of said plurality of subsystem resident agents, exchange said information with said diagnosis agent and transmit said diagnosis agent back to said adaptive global agent.