Ferroelectrics are materials that exhibit a switcheable polarisation, i.e. a net displacement of positively charged cations relative to anions that is reversible. In traditional "proper" ferroelectrics, this property is usually associated with the electronic structure of particular cations, but the field has been shaken recently by the discover of the "hybrid-improper" mechanism for ferroelectricity, in which different types of structural changes can be coupled to give rise to this property. We've been working on some materials with the potential to show ferroelectricity by this new mechanism, but our experiments have revealed some disorder in their crystal structures. We believe that this disorder is related to the very same structural changes associated with the mechanism, and neutron scattering experiments to study this are needed to fully understand this behaviour.