There are many suggested solar-terrestrial relationships in global atmospheric electricity. Of the various relationships, the downward mapping of ionospheric and magnetospheric electric fields, associated with the solar wind/magnetosphere and the ionosphere wind dynamos, is best understood theoretically and appears to be supported by the few available data. The solar cycle variations of ionospheric potential and air-earth current appear to be related to variations in galactic cosmic rays and perhaps to their effect on the current output from thunderstorms. The solar flare and solar magnetic sector boundary variations are not well understood but may be related to Forbush decreases in cosmic ray flux and/or effects resulting from energetic particle precipitation. The available data on auroral effects on atmospheric electricity are confusing and not understood at all. There is a clear need for further research to better define the physical mechanisms responsible for all of these solar-terrestrial relationships. The observed solar-terrestrial variations and the need for current closure in the global circuit suggest that the function of the equalization layer in the ''classical picture'' of atmospheric electricity should be revised to be consistent with our current knowledge of upper-atmospheric electrical processes.