The stars in the FK4- and FK4Sup-Catalogue are supplied with visual magnitudes and spectral types essentially on the basis of the Henry Draper Catalogue. There are several good arguments, to compile additional astrometric, photometric and spectroscopic data for these stars. Not only to detect astrometric effects, which can produce errors in the fundamental system, like magnitude equation, colour equation, and foreshorthening effect. For the last one distances and radial velocities have to be known. But also to study the kinematics of the FK4/FK4Sup stars, in profiting from their high precision in proper motion.