A combination manual/pneumatic shut-off valve (11) is disclosed. The valve comprises a housing (13); a valve chamber (17) which is disposed in the housing and which has a fluid inlet (19) and a fluid outlet (21); a diaphragm (23); a valve seat (25); a pneumatically driven actuator (29) which is adapted to move the diaphragm from a first position in which the diaphragm and the valve seat form a seal between the fluid inlet and the fluid outlet, to a second position in which the fluid inlet and fluid outlet are in open communication with each other; and a handle (31) adapted to manually move the diaphragm from the second position to the first position by way of the actuator, independently of the pneumatic control signal. The valve allows the length of process fluid control assemblies, and hence the size of fluid panels, to be reduced by combining the functionalities of a manual valve and a pneumatic valve into a single element.