This volume contains the texts of the invited lectures presented at the NATO Advanced Study Institute ‘Theory of Solar and Planetary Dynamos’ held at the Isaac Newton Institute for Mathematical Sciences in Cambridge from September 20 to October 2 1992. Its companion volume ‘Solar and Planetary Dynamos’, containing the texts of the contributed papers, has recently been published in the same series as the present one, and contains a full list of participants and their addresses. It is a measure of the recent growth of the subject that one volume has proved insufficient to contain all the material presented at the meeting: indeed, dynamo theory now acts as an interface between such diverse areas of mathematical interest as bifurcation theory, Hamiltonian mechanics, turbulence theory, large-scale computational fluid dynamics and asymptotic methods, as well as providing a forum for the interchange of ideas between astrophysicists, geophysicists and those concerned with the industrial applications of magnetohydrodynamics.

The topics of the lectures cover almost all the principal parts of the subject. Authors were asked to give reviews of a pedagogical nature. Earlier chapters cover relatively fundamental aspects of the subject; later chapters treat more specialised topics. Although each chapter is self-contained, there are cross-references to other lectures where appropriate; in addition, the Editors have striven to maintain uniformity of notation and style, in the hope that the resulting complete text will find favour as a unified work of reference, rather than as a disparate set of reviews.