This book opens with an overview of the fundamentals and applications of the young and fast developing area of transition metal catalysed/mediated oxidative (dehydrogenative) C-H/C-H coupling reactions between two (hetero)arenes. Continuing, the authors highlight the recent advances reagarding the ligand supported transition metal-catalysed domino (cascade) or one-pot syntheses of various heterocycles involving cross-coupling reactions. The recent advances in Cu catalysed tandem reactions for heterocycle synthesis are also addressed. Cu metal chemistry has garnered attention as a potential alternative to precious transition metals, being cheaper, more sustainable and more easily available. A comprehensive account of research on green chemical routes is provided, involving various palladium metal-based catalysts utilised in facilitating cross-coupling reaction in aqueous media. Reported decarboxylative cross-coupling reactions are discussed along with suitable examples, focusing on their mechanism of action.