Ferroelectricity can emerge in vertically stacked two-dimensional materials even when their constituent monolayers are nonferroelectric. In these sliding ferroelectrics, polarization switching is driven by small lateral displacements between layers. Here, we develop a comprehensive materials design framework for slidetronics founded on a symmetry principle: any sliding-induced polarization change from a state $\mathit{P}$ to ${\mathit{P}}^{\prime }$ can be equivalently described by applying an appropriate point-group operator, or “generator” $G$, to the entire system, such that ${\mathit{P}}^{\prime }=G\mathit{P}$. This generator-based framework classifies all possible sliding-induced transformations, establishes the necessary symmetry conditions for switchable polarization components, and provides design strategies for realizing targeted switching behaviors. A central result is that complete polarization inversion is symmetry forbidden in bilayers but becomes possible in multilayers. First-principles calculations confirm these predictions, revealing novel phenomena including dipole-locked ferroelectricity in cellulose bilayers, in-plane switching in ${\mathrm{As}}_2{\mathrm{S}}_3$-based systems, and full polarization reversal in a ${\mathrm{PdSe}}_2$ trilayer.

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• Ferroelectricity
• Layered crystals
• Discrete symmetries in condensed matter