Most observers of the geophysical scene, those involved with plate tectonics and continental drift in particular, are aware of the seminal contributions of rock magnetism and its sister discipline, paleomagnetism, which some have called “applied rock magnetism.” That was in the heady days of the 1960s. As a discipline, however esoteric, rock magnetism goes further back to the 19th century when the Swedish prospectors for iron ores and Italian and German paleomagnetists in search of the history of the geomagnetic field were using rock magnetism as an exciting new tool. The first book on rock magnetism, Der Gesteinsmagnetismus by H. Haalck, was published in 1942, more than a decade before T. Nagata's Rock Magnetism, cited by Dunlop and Ozdemir as the earliest work on the subject. There have been more recent volumes on the subject, including one that I coauthored with Frank Stacey. However, I am not exaggerating when I say that Rock Magnetism: Fundamentals and Frontiers leaves the others in the dust.