One century after the discovery of ferroelectricity, and two decades after ferroelectric random access memories were first commercialized, this Special Issue of Advanced Electronic Materials demonstrates that the field of ferroelectricity is in robust health. First, ferroelectricity arises in very different types of material via different mechanisms. Second, ferroelectric domains in each type of material are liable to switch differently, for both intrinsic reasons (chemical formula) and extrinsic reasons (microstructure/strain). Third, an electrical polarization can display complex topologies. Fourth, ferroelectric order parameters can couple to other order parameters, e.g. magnetic order parameters. Fifth, ferroelectrics can be modified using light. Sixth, there continue to be improvements in techniques that measure ferroelectric and other ferroic materials. Seventh, ferroelectrics continue to attract the attention of experimentalists and theorists alike. We thank all of these people for their wonderful contributions, and below we identify papers via the name of the person invited. Last, we thank Dr Gaia Tomasello for suggesting the topic and inviting us to be Guest Editors. It has been a pleasure working with her.