Liquid crystals have become ubiquitous in the displays for electronic devices, ranging from wrist watches to laptop computers. Nuclear magnetic resonance is one of the important mechanisms for determining their structures tures and properties. This book covers NMR techniques used in studying liquid crystals and present up to date results from such studies. Ronald Dong has worked on NMR in liquid crystals for much of his professional career. Topics covered include: Nuclear spin dynamics, orientational order, molecular field theories of liquid-crystal molecules, nuclear spin relaxation, spin relaxation, rotational and translational dynamics, internal dynamics of liquid-crystal molecules, NMR in liquid crystals; an appendix covers rotations, Euler angles and Wigner rotation matrices.