A control apparatus for downhole flow control devices: the apparatus comprising first and second modules (19,21), wherein each module is operable to fluidly connect with a respective downhole flow control device (15, 17): each module comprises two inlet ports (27; 29, 35;37) and two outlet ports (31, 33, 39, 41); wherein one inlet port (27, 35) of each module is adapted to fluidly communicate with a first control line located above and the other inlet port (29, 37) of each module is adapted to fluidly communicate with a second control line located above; the first module being operable to open and close a first downhole flow control device on application of fluid pressure through the first control line; and the second module being operable to open and close a second downhole flow control device on application of fluid pressure through the second control line; wherein each module comprises a switching member defining a fluid flow path and under application of fluid pressure from one of the first or second control lines the switching member is operable to direct fluid pressure to one of the two outlet ports to activate opening one of the first or second downhole flow control devices, and under application of fluid pressure from the one of the first or second control lines the switching member is operable to direct fluid pressure to the other of the two outlet ports to activate closing the one of the first or second downhole flow control devices. the apparatus comprising first and second modules (19,21), wherein each module is operable to fluidly connect with a respective downhole flow control device (15, 17): each module comprises two inlet ports (27; 29, 35;37) and two outlet ports (31, 33, 39, 41); wherein one inlet port (27, 35) of each module is adapted to fluidly communicate with a first control line located above and the other inlet port (29, 37) of each module is adapted to fluidly communicate with a second control line located above; the first module being operable to open and close a first downhole flow control device on application of fluid pressure through the first control line; and the second module being operable to open and close a second downhole flow control device on application of fluid pressure through the second control line; each module comprises two inlet ports (27; 29, 35;37) and two outlet ports (31, 33, 39, 41); wherein one inlet port (27, 35) of each module is adapted to fluidly communicate with a first control line located above and the other inlet port (29, 37) of each module is adapted to fluidly communicate with a second control line located above; the first module being operable to open and close a first downhole flow control device on application of fluid pressure through the first control line; and the second module being operable to open and close a second downhole flow control device on application of fluid pressure through the second control line; wherein each module comprises a switching member defining a fluid flow path and under application of fluid pressure from one of the first or second control lines the switching member is operable to direct fluid pressure to one of the two outlet ports to activate opening one of the first or second downhole flow control devices, and under application of fluid pressure from the one of the first or second control lines the switching member is operable to direct fluid pressure to the other of the two outlet ports to activate closing the one of the first or second downhole flow control devices.