During 1985 and 1986, a Gulf of Mexico ring shed by the Loop Current was observed to migrate toward the western Gulf of Mexico. This movement across the gulf was well documented by observations that included drifter data within and outside the ring, sea surface temperature at weekly intervals, expendable bathythermograph surveys at various times, one major hydrographic cruise when the ring was in the northwestern gulf, and currents from moorings over which the ring passed. The drifter data were used to infer the movement of the ring center as well as the eccentricity and orientation of the major axes. The data from the drifters bridge the gaps between detailed surveys to the extent that a daily history of the position and shape of the ring can be constructed. The synthesis of these diverse but complimentary data sources provides a detailed description of how the ring interacted with the bathymetry of the northern Gulf of Mexico as well as the previously and subsequently shed rings. ¿ American Geophysical Union 1989