An ablutionary fitting controller comprising a push-button actuator (200, 1200) arranged to mechanically actuate a valve so as to control a flow of water to an outlet, wherein the push-button actuator (200, 1200) comprises: a button (202, 1202) comprising a contact surface (202a, 1202a), and arranged to be moved in a longitudinal direction by a force applied to the contact surface (202a, 1202a), the button (202, 1202) further comprising one or more surfaces inclined with respect to the longitudinal direction; a cam member arranged to be pushed in the longitudinal direction by movement of the button (202, 1202), and comprising one or more surfaces inclined with respect to the longitudinal direction, wherein the inclined surfaces of the button (202, 1202) are arranged to interact with the inclined surfaces of the cam member so as to cause the cam member to rotate as it is pushed in the longitudinal direction; a button housing (204, 1204) at least partially surrounding the button (202, 1202) and cam member and comprising one or more surfaces inclined with respect to the longitudinal direction and arranged to interact with the inclined surfaces of the cam member so as to cause the cam member to rotate as it moves in the longitudinal direction, and wherein, when the applied force is removed, the button housing (204, 1204) is arranged to hold the cam member in either a first position in which the valve is open or a second position in which the valve is closed, depending on the angle of rotation of the cam member; an over-travel member (205, 2205) mounted on the cam member and extending beyond the cam member in the longitudinal direction away from the contact surface (202a, 1202a) of the button (202, 1202), wherein the over-travel member (205, 2205) is arranged to push a valve connection member in response to the applied force so as to mechanically actuate the valve; a first biasing member (207, 1207, 2207) arranged to bias the over-travel member (205, 2205) in the longitudinal direction away from the contact surface (202a, 1202a) of the button (202, 1202); and a second biasing member arranged to bias the button (202, 1202) away from the button housing (204, 1204), wherein the first and second biasing members are springs oriented along the longitudinal direction, and wherein the first biasing member (207, 1207, 2207) is arranged to lie at least partially within the second biasing member in at least one of the first position and the second position, characterised in that the second biasing member is mounted between the button housing (204, 1204) and the button (202, 1202) and encircles at least a portion of the cam member. a cam member arranged to be pushed in the longitudinal direction by movement of the button (202, 1202), and comprising one or more surfaces inclined with respect to the longitudinal direction, wherein the inclined surfaces of the button (202, 1202) are arranged to interact with the inclined surfaces of the cam member so as to cause the cam member to rotate as it is pushed in the longitudinal direction; a button housing (204, 1204) at least partially surrounding the button (202, 1202) and cam member and comprising one or more surfaces inclined with respect to the longitudinal direction and arranged to interact with the inclined surfaces of the cam member so as to cause the cam member to rotate as it moves in the longitudinal direction, and wherein, when the applied force is removed, the button housing (204, 1204) is arranged to hold the cam member in either a first position in which the valve is open or a second position in which the valve is closed, depending on the angle of rotation of the cam member; an over-travel member (205, 2205) mounted on the cam member and extending beyond the cam member in the longitudinal direction away from the contact surface (202a, 1202a) of the button (202, 1202), wherein the over-travel member (205, 2205) is arranged to push a valve connection member in response to the applied force so as to mechanically actuate the valve; a first biasing member (207, 1207, 2207) arranged to bias the over-travel member (205, 2205) in the longitudinal direction away from the contact surface (202a, 1202a) of the button (202, 1202); and a second biasing member arranged to bias the button (202, 1202) away from the button housing (204, 1204), wherein the first and second biasing members are springs oriented along the longitudinal direction, and wherein the first biasing member (207, 1207, 2207) is arranged to lie at least partially within the second biasing member in at least one of the first position and the second position, characterised in that the second biasing member is mounted between the button housing (204, 1204) and the button (202, 1202) and encircles at least a portion of the cam member.