Abstract: An automated analysis system includes a pair of sample selection subsystems whose operations are coordinated by a host computer pursuant to developing analytical data useful to a process computer in controlling an industrial process. Each subsystem includes a sample selection computer operating to control one or more multiport valves in extracting fluid samples on a scheduled or demand basis from sample loops connected with the various process streams involved with the process. The extracted samples are injected into a spectrometer for analysis. An instrument computer converts the spectrometer responses to analytical data indicative of the constituent concentrations found in an analyzed sample.