Abstract: A multiport, diaphragm-sealed valve suitable for use in sampling systems. Using a rotational movement, which can be electrically controlled, the valve operates without leakage or intermingling of transfer fluids to provide a simultaneous seal of all fluid pathways during the switching of flowpaths. multiport, diaphragm-sealed valve suitable for use in sampling systems. Using a rotational movement, which can be electrically controlled, the valve operates without leakage or intermingling of transfer fluids to provide a simultaneous seal of all fluid pathways during the switching of flow paths.