This paper is a preliminary, abridged review of current ideas regarding mobile ionic species in polymer electrets. The chief concept is that much of the persistent electrical polarization, developed in polymers prepared for piezo- or pyroelectric applications, is due to displaced ions. It is recognized that 1) preferential orientation of dipolar parts of the macromolecules (e.g., side groups) and 2) fluctuations in supermolecular order (including crystalline regions) lead to inhomogenieties in internal electrical fields which affect where such mobile ions become stabilized (trapped). Emphasis is placed on results obtained recently from research on polyacrylonitrile electrets. (Author)

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