This project is for the theoretical investigation of convective plasma transport and ionosphere-magnetosphere coupling in the outer planets Jupiter, Saturn, Uranus and possible Neptune. The magnetospheres of Jupiter and Saturn are driven by internal sources of plasma from embedded satellites. The energy from the planetary rotation plays an important role. The magnetosphere of Uranus is driven by the solar wind, a familiar situation like the terrestrial magnetosphere. However, the planetary rotation is still very important. In all of these magnetospheres, convection is regulated by electrodynamic coupling to the ionosphere. In order to investigate these processes, numerical modeling will be used. To guide the modeling effort, the observations from the Voyager experiments of plasma and magnetic field will be used. The comparative study of the various planetary magnetospheres will enhance our understanding of terrestrial magnetosphere-ionosphere coupling processes.