This book describes the synthesis of cross-linked LC materials, as non-oriented and oriented systems. Potential applications are described: actuators or artificial muscles, optics, and imprinted materials for separation. Although the physics of these materials has been the topic of other books, there has not been a single book devoted to the chemistry of cross-linked LC materials. The developments toward the preparation of micro and nano systems can be seen as a sign that the field is gaining more and more interest, in conjunction with other domains such as microfluidics.