Dynamic Nuclear Polarized (DNP) solid targets are in operation for their use in nuclear and particle physics experiments since the early 1960`s at various laboratories. Early developments in cryogenics and magnet technologies have led to proton polarization values close to 100% in a variety of target materials already in the 1970`s. Radiation doping as well as new chemical dopants for thr DNP process improved the polarization degree for deuterons with their rather low gyromagnetic ratio drastically. The state of the art for highly polarized solid deuteron targets will be given. The talk will end with very short remarks to recent spin-off activities from polarized solid targets in the field of medicine.