Technetium-99m radiopharmaceuticals are widely used in diagnostic nuclear medicine as radioactive tracers for detecting pathological states of internal organs of the body. The development of a new diagnostic agent has been always intimately connected with advances in the knowledge of the basic chemistry of technetium. In this article, a recent advancement in the study of the chemistry of technetium complexes containing a terminal Tc≡N multiple bond and the resulting applications to the preparation of the first ex- amples of nitride technetium-99m radiopharmaceuticals are shortly reviewed. Specifically, a new method for the syntesis of complexes containing the Tc≡N group by reaction of the pertechnetate anion with derivatives of dithiocarbazic acid is described. An illustration of the structure and properties of various classes of radiopharmaceuticals which have been prepared through the new procedure is also reported.