This highly readable monograph is an extensive revision of an earlier book published in 1969 by John Wiley. Piddington clearly loves his subject matter and writes with enthusiasm about the role and critical importance of magnetic fields in the universe around us. He treats solar magnetic fields, the interplanetary medium, the magnetosphere, planetary magnetospheres, and galactic magnetic fields. The treatment is far from uniform, and the topical balance has shifted somewhat from that in the first edition to that in the second. For example, in the first edition there were 27 pages devoted to solar magnetism, and in the second 81 pages. In the first edition there were three chapters devoted to geomagnetism and in the new edition two.