Coal seam gas problems, largely “gas-outs” and instantaneous outbursts of coal and gas, have created serious difficulties for the coal mining industry around the world. Typically, a single longwall face is now capable of producing an average 10 000 to 15 000 tonnes of coal per day. The total quantity of gas released in gassy mines could conceivably reach 5000 and 8000 litres of gas per second per single longwall block and for the total mine respectively. The introduction of various gas drainage techniques in Australian gassy mines was necessary to complement ventilation systems and to satisfy the statutory gas limitation in underground workings. Methane drainage can simultaneously reduce the risk of dangerous methane concentrations accumulating as well as reducing methane emissions into the atmosphere; moreover, the methane recovered is a valuable energy source and can be used to considerable economic effect.