Magnetic fields affect the evolution of the Universe on all scales from the Sun to galaxy clusters. They provide nearly as much energy into the interstellar medium as gas motions or thermal heating, are essential to star formation and contribute enormously to the total pressure of interstellar gas. And yet, we know very little about the origin of magnetic fields within galaxies or indeed the nature of magnetised gas in galaxies. This project will work with a new radio interferometric survey from the Australia Telescope Compact Array of polarized extragalactic sources to probe the magnetised, ionised medium throughout the nearest galaxies, the Large and Small Magellanic Clouds. We will make the most precise measurements of the magnetic field in these galaxies and how they vary with position. This project will carry on into the Australian SKA Pathfinder Polarization survey of the Universe’s Magnetism (POSSUM) and will involve collaboration with researchers at the Max Planck Institute for Radioastronomy in Bonn, Germany and the University of Toronto, in Canada.