These volumes are an abstraction from the Encyclopedia of Nuclear Magnetic Resonance of articles concerned with magnetic resonance imaging and spectroscopy. The volumes cover imaging in all its forms, and spectroscopy in as far as it relates to in vivo studies, and clinical applications involving in vitro investigations of tissue. The various articles which comprise these two volumes are organised into topic-based sections. Some of the articles appear as they were originally presented in the Encyclopedia, where there is little new information, and some have been more or less substantially revised in the light of what has happened since the articles were first written. A number of new articles have been added where topics have either developed from fragmentary discussions in the early 1990s, or have been created ab initio since the publication of the Encyclopedia. These extensive volumes are unique in their coverage, with a balance between imaging physics, spectroscopy and clinical studies. In many ways, they reflect the scope covered by the major international in vivo NMR Societies, with a conscious effort to allow the reader to understand all the elements that make up modern clinical magnetic resonance. Equally, the topic is so huge, and still evolving so fast in detail, rather than concept, that they can act as no more than an introduction, though at quite a demanding level. The reader will appreciate the extent, nature and dynamics of human and animal magnetic resonance, and will have the route map to allow them to find any further information they may need.