Abstract: A novel gas lift apparatus is described which is particularly useful for the dewatering of gas wells in which the gas pressure is low or for the lifting of oil from wells when mixed oil and gas are produced. Water or oil is allowed to collect in the tubing above the valve of the apparatus. Sensors provide indications of the water level or the hydrostatic head within the tubing, and of the gas pressure in the casing. The outputs of the sensors are fed to an electronic, pneumatic or hydraulic controller which at a predetermined differential pressure opens the valve. Alternatively, a timer can be used to energize the valve at a predetermined time.