"Nuclear medicine is the medical specialty that utilizes the nuclear properties of radioactive and stable nuclides to make diagnostic evaluation of the anatomic or physiologic conditions of the body and to provide therapy with unsealed radioactive sources. The skills of the nuclear medicine technologist complement those of the nuclear medicine physician and of other professionals in the field."

(from the Essentials and Guidelines for an Accredited Educational Program for the Nuclear Medicine Technologist, Section II: Specific Requirements.)