A survey of the interstellar medium in the Milky Way and Magellanic Clouds using the Australian Square Kilometre Array Pathfinder. Between the stars in the Milky Way there are clouds of gas and dust; old stars eject heavy elements into this interstellar medium, and new stars form when interstellar clouds collapse under their own gravity. This survey is making maps of the interstellar gas using spectral lines at radio wavelengths to trace the cycle of star formation.