In recent years, there has been increasing awareness of the importance of large‐scale electric fields in the earth's magnetosphere. Much attention has been directed to the quasi‐static electric field associated with charge separations generated by solar wind‐magnetosphere interaction, but these seem inadequate to explain many important processes. This paper reviews the evidence for the inclusion of electric fields of inductive origin, i.e., those due to time‐dependent currents in the magnetosphere‐ionosphere system. Attention is focused on processes associated with magnetospheric substorms, as they are well characterized by various types of evidence and do involve events such as energetic particle precipitation which require explanation beyond that provided by static electric field models. It is found that inductive electric fields are significant at times and should be included for a proper description of observed events.

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