A 5-year program is outlined to use GOES-5, -6, and -7 geosynchronous magnetic field observations to determine the characteristics of the solar wind-magnetosphere interaction. A linear prediction filter analysis of the dayside magnetospheric magnetic field strength will determine the time scales and lags associated with the response to variations in the north-south component of the IMF, the IMF cone angle, and the solar wind dynamic pressure. A Fourier decomposition of the geosynchronous magnetic field observations will determine the effects of these solar wind parameters upon the diurnal variation of the magnetospheric magnetic field. We will use the results so obtained to discriminate between several suggested modes for solar wind- magnetosphere interaction and to extend models for the dayside magnetopause to more extreme values of solar wind parameters. We propose a plan to use variations in the east-west component of the magnetospheric magnetic field to distinguish between component and antiparallel modes of dayside merging as a function of solar wind conditions. Finally, we combine solar wind, geosynchronous, and ground observations to study the effects of north/south IMF turnings and solar wind dynamic pressure variations upon low- latitude dayside ground magnetograms in an effort to determine the cause of the enhanced H components seen in low-latitude ground magnetograms during DP2 convection pattern variations.