Ghez' research employs high spatial resolution imaging techniques, such as the adaptive optics system at the Keck telescopes, to study star-forming regions and the supermassive black hole at the center of the Milky Way known as Sagittarius A*. She uses the kinematics of stars near the center of the Milky Way as a probe to investigate this region. The high resolution of the Keck telescopes gave a significant improvement over the first major study of galactic center kinematics by Reinhard Genzel's group.