Mean values for gravity and potential at the surface of the Earth are derived for limited areas in terms of mean anomalies using the cross-track and radial components of the E¿tv¿s tensor derived from space-borne gradiometer data at satellite altitude. Stability, resolution, and precision are investigated, and reliability criteria are established. The inverse boundary value problem is discussed for specific solutions for smaller and larger areas at the Earth's surface; discrete area means and point values are considered. ¿ American Geophysical Union 1993