Modified atmosphere techniques for grain storage have been under syudy in Australia for over 60 years but until recently have been widely used only during one brief period (1917-1919). Full scale testing of nitrogen-based atmospheres, started in 1972, and has led to development of a process, based on a tanker-delivered liquid nitrogen, similar to that developed by Snamprogetti in Italy. Since, under dry Australian conditions, the quality of grains such as wheat is maintained adequately in storage, the emphasis in the use of nitrogen-based systems has been on insect rather than quality control. More recently the use of CO₂ has been investigated. CO₂, at present, is the preferred atmosphere for insect control as it is easy to apply and, unlike nitrogen atmospheres, does not require a continuous input of gas after the initial purge if the storage is well sealed. CO₂-based atmospheres are now in use in Australia for insect control in stored grain. A summary of the unpublished experimental and commercial trials carried out with modified atmospheres in Australia is given. If insect control only is required, it should only be necessary to maintain the modified atmosphere until elimination of insects is achieved. The sealed fabric of the storage should then provide a barrier against reinfestation. This proposition is discussed and examples of storage free of insects for more than four months after brief modified atmosphere treatment are given.