  The results of a kinematical population classification of 497 Hipparcos
orbital binaries are discussed. Less than 10% of the stars from the sample
belong to the thick disk. Only seven stars have halo kinematics. There are no
direct dynamical mass determinations for extreme halo stars. Some suggestions,
concerning Population II visual binaries for which ground-based astrometric
observations in combination with GAIA data will be useful in the future for the
better determination of orbits for long period Population II binaries, are
offered.
