Objectives

High accuracy astrometry has made spectacular progress over the past decade thanks to developments in VLBI techniques, the appearance on the scene of the GRAVITY instrument, and the giant step taken with the Gaia mission in the quality and depth of its astrometric survey. High accuracy astrometric data is now indispensable across astronomy disciplines and in solar system science. With this focus meeting we wish to highlight the scientific progress based on these astrometric data and bring together the various astrometry and sky survey communities; to learn from each other, explore opportunities for coordination and map out the synergies between astrometry and other techniques and surveys, aiming to maximize the scientific outputs. The IAU GA is the natural venue to bring the communities together and the timing is right, one year after the appearance of the early part of the third Gaia release, three years after the adoption of the ICRF-3, five years into GRAVITY operations, and on the eve of the era of LSST and extremely large telescopes.