Metal-containing compounds for the treatment of numerous diseases or their prevention, as well as for imaging and diagnosis of disease states of an organism, represent important tools in contemporary medicine. Applications and developments of metal compounds in cancer chemotherapy, uses against inflammations and infections, strategies against diseases caused by an excess of metals, and new strategies to employ nanoparticles in medicine will be presented, among others. Highlights reflecting the clinical roles of metal complexes are the highly successful platinum anticancer drugs and the metal compounds used for magnetic resonance imaging.