This up-to-date review closes an important gap in the literature by providing a comprehensive description of the M?auer effect in lattice dynamics, along with a collection of applications in metals, alloys, amorphous solids, molecular crystals, thin films, and nanocrystals. It is the first to systematically compare M?auer spectroscopy using synchrotron radiation to conventional M?auer spectroscopy, discussing in detail its advantages and capabilities, backed by the latest theoretical developments and experimental examples.