Ferroelectric liquid crystals (FLCs) have great potential in the future development of high-resolution displays. A key requirement for their application is an understanding of the relationship between the molecular structure of the liquid crystals and their spontaneous polarization (P(s)) which in turn influences the switching speed of the materials. Here, it is shown that bulky substituents, which hinder rotation about the long axis of the mesogens (see figure) lead to a higher P(s).