1 Presentation of Astrometry.- 2 Image Formation.- 3 Atmospheric Effects on Image Formation.- 4 Reduction of Observations.- 5 Small-Field Astrometry.- 6 Meridian Circles.- 7 Equal Altitude Instruments.- 8 Hipparcos.- 9 Very Small Field Astrometry.- 10 Phase Interferometry.- 11 Timing Techniques.- 12 Future of Astrometry.- References.

An introduction to practical astrometry, dealing with the determination of positions, motions, distances and dimensions of celestial bodies ranging from quasars to artificial satellites. For this 2nd edition, the release of the Hipparcos and Tycho catalogs, the rise in CCD astrometry and the adoption of a new celestial reference frame by the IAU led to a significant modification of the text. And, especially, the outlook for astrometry has been completely rewritten.