Field-gradient NMR applications in liquid crystals (LCs) are dominantly experiments that detect the translational self-diffusion of the various structural units of the liquid crystalline phases. The anisotropy of LCs often leads to line broadening effects that must typically be suppressed in order to accommodate sufficient gradient dephasing of the nuclear spins. Having dealt with this problem, diffusion studies provide important insights into both lyotropic and thermotropic liquid crystal systems.