Interferometry and the study of binaries
  To determine the parameters (masses, orbital period) of a binary, one requires among others the inclination, which is best determined from a visual orbit. The next generation of interferometers can provide visual orbits for a large number of binaries. We then can investigate with what parameters binaries are born, and how these parameters evolve, and thus understand the galactic binary population. Results can be obtained quickly by carefully selecting binaries for the study of evolutionary processes. Full knowledge of properties of binaries at birth requires a large, dedicated programme, which is best limited to spectroscopic binaries with primary masses >0.8Msun and orbital periods <50yr. 
Frank Verbunt