Polymer-dispersed liquid crystals (PDLC) are widely used for electro-optic applications such as flexible displays, privacy windows or projection displays. Besides these applications, the confinement of a liquid crystal to small cavities is of fundamental interest. The present paper contains a review of the work on nematic and cholesteric PDLCs. Moreover, some very recent developments are summarized such as the use of ferroelectric liquid crystals for PDLC applications.