This account summarizes representative contributions of Prof. Naomichi Furukawa to the field of heteroatom chemistry. Ligand‐coupling reactions (LCRs) and ligand‐exchange reactions (LERs) of chalcogen derivatives were developed from reactions of trivalent chalcogen species with organometallic reagents. Prof. Furukawa has also reported a large number of mono‐ and dicationic compounds generated via transannular and intermolecular interactions. Furthermore, the detection and isolation of hypercoordinated chalcogen species bearing only carbon ligands and an efficient method for the synthesis of thiophene S‐oxides and their reactivity are described.