I will present a measurement of the galaxy correlation function at z=0.57 from the BOSS DR9 sample. The baryon acoustic oscillation feature (BAO) is detected with high significance, and provides the most precise distance constraint ever obtained from a galaxy survey (1.7%). Further cosmological tests are available from the relative amplitude of clustering along and perpendicular to the line of sight. The Alcock-Paczynski effect allows a geometric test to measure the product of the angular diameter distance and Hubble expansion rate at the galaxy sample's redshift. Peculiar velocities of galaxies also amplify the apparent clustering along the line-of-sight. We demonstrate our ability to distinguish these effects in the data through their scale-dependence, and present measurements of both the growth of structure, the angular diameter distance, and the Hubble expansion rate at z=0.57, along with their cosmological implications.