The idea behind this book originated at a meeting held in Caramulo in Portugal in
September 2003. The participants agreed that, though the field of natural dynamos
(planetary, stellar and galactic) was rapidly evolving and attracting the interest of
researchers in other branches of fluid mechanics, there was no comprehensive introductory
book for researchers or graduate students entering this research area. The
organisers therefore decided to take advantage of the broad-based knowledge of the
invited lecturers at the conference to assemble a “multi-authored monograph”. Despite
the obvious contradiction in this phrase, it does reflect the spirit in which this
book was prepared. While each section of the book was written by specialists in different
aspects of this subject, a concerted effort has been made to provide a unified
presentation, which develops concepts in a coherent order and, where feasible, uses
consistent notation.