This article briefly summarizes recent progress on the luminescence studies of monomeric, multinuclear, and polymeric Zn(ii)/Cd(ii) coordination complexes, involving spectroscopic, photophysical, and photochemical studies, as well as molecular and electronic structural investigations, focussing mainly on the interplaying factors that govern the luminescent origin of the lowest-lying emissive states. Current results show that, for Zn(ii)/Cd(ii) coordination complexes in general, the nature of the metal centres and ligands and the rigid metal-oxy (or -hydroxy) clusters are factors governing their luminescent origin of the lowest-lying emissive states; different types of ligands and coordination structures may result in different emission mechanisms.