William van Altena is Professor Emeritus in the Astronomy Department, Yale University, and has taught undergraduate and graduate courses in introductory astronomy, astronomical observing and astrometry for over 40 years. He served as Director of the Yerkes Observatory, Chair of the Yale Astronomy Department and was Team Leader for the Hubble Space Telescope's Astrometry Instrument Definition Team and a member of the HST Astrometry Science Team. His current research involves studies of the kinematical structure of the Milky Way in the Southern Hemisphere, binary stars and the use of high technology cameras to study galaxy remnants that are merging with the Milky Way.