Materials with long range ferroelectric or magnetic order are important for applications including data storage, and a current key research area in functional materials is the design and preparation of materials that combine both these properties. A family of ceramic oxides, the Aurivillius family, are well known for their ferroelectric properties and until now, attempts to introduce magnetic ions into these materials have been limited. In 2018, a new Auriivillius oxide-fluoride, Bi2CoO2F4, was reported. This is exciting because it has long-range magnetic order, and the potential to display ferroelectric properties. Neutron powder diffraction will allow us to investigate its magnetic order, as well as its structural behaviour, helping us understand its properties.