This book presents a major research program on epigenetic mechanisms of cell programming and reprogramming. The program was launched by the National Natural Science Foundation of China during the 11th Five-Year Plan period, which was started in October 2008 and concluded at the end of 2016. It first summarizes the epigenetic research plans and the current situation of epigenetic research in China and the international frontier. With the application of interdisciplinary research methods, the book discusses the development trends of epigenetic research, such as mechanisms of establishment and maintenance of epigenetic information and epigenetic regulation on reproduction and development. It also presents a variety of research achievements. For example, the discovery of new epigenetic regulators and chromatin remodulaters and their biological functions and mechanisms are highlighted. Several regulation mechanisms of cell differentiation and trans-differentiation are discussed, especially the discovery of the key factors to promote the trans-differentiation of somatic cells to hepaytes. In addition, this book puts forward some key academic fields with increasing importance, such as biochemistry, cell biology, and clinical medicine. Given its scope, the book is of interest to researchers who work in cell biology, biochemistry, structural biology, bioinformatics, clinical medicine, and other related fields.