This book discusses the developments in the synthesis and functionalization of different heterocycles based on the formation of carbon-carbon (C-C) and carbon-heteroatom (C-X) bonds using cross-dehydrogenative coupling (CDC). Consisting of 13 chapters, the book systematically describes the advances in the synthesis and functionalization of nitrogen, oxygen, and sulfur-containing heterocycles. It also discusses the various mechanistic pathways to help readers gain an in-depth understanding of the CDC reactions of heterocycles. Lastly, in order to promote green chemistry, it addresses a range of metal-free CDC reactions of heterocycles – an area that has attracted significant attention in both academic and industrial research.