At the Radcliffe Observatory, Dr. Feast and I have recently compiled a third list of radial velocities of O and B stars which was designed primarily to push our optical knowledge of the dynamics of the Galaxy to great distances from the Sun (Feast and Thackeray 1963). This program was preceded by the determination of distance moduli of 248 O and B stars in cooperation with Dr. Stoy of the Royal Observatory, Cape, and Dr. Wesselink at the Radcliffe Observatory (Feast et al. 1961). As a result of this work we now have radial velocities for a very considerable number of southern stars at distances greater than 2 and even 3 kpc. It is quite possible that many of these distances are overestimated and it is highly desirable that the distances should be improved by the Walraven multicolour method or by some other technique. In the meantime it can certainly be claimed that our knowledge of radial velocities of these distant stars is considerably better in the southern than in the northern hemisphere.