Iodonium imides (ArINR) represent an important class of hypervalent iodine(III) compounds recently emerging as versatile, efficient and environmentally friendly synthetic reagents with numerous applications in academic and industrial research. Iodonium imides, which are also known as iminoiodanes, are widely used in organic synthesis as common nitrene precursors in the aziridination of alkenes and the amidation reactions of various organic substrates. In the present review, the preparation and structural features of iminoiodanes are discussed, and recent developments in their synthetic applications are summarized.