The progress of magnetic resonance imaging (MRI) as a clinical tool has been extraordinary, out-stripping the rate of development of any other imaging technique. This speed of growth is a testimony to its clinical significance. Medical imaging specialists and their clinical colleagues have not been slow to grasp the advantages of an investigation which produces clear anatomical display in any plane, with no radiation risk to the patient, and with a tissue discrimination unrivalled by any other imaging technique. This process has accelerated rather than achieving a plateau and new clinical applications are constantly being defined. Any new imaging technique brings with it an educational need, which in the case of MRI, is intense. The underlying technology is particularly complex and a working knowledge of it is essential to good practice. A case in point is fast imaging, which promises to change radically many of our diagnostic approaches. The radiologist, therefore, needs the support of technologists who are not only capable but also well informed to a degree not required in other radiological work; MRI is without doubt the modality where the changing dynamics of the technology and applications create our greatest challenges for continuing education. The success of the first edition of this book is not surprising, considering the need and the fact that it was written not by scientists or radiologists for technologists, but by two technologists both actively involved in MRI, not only in clinical imaging but also in teaching their art to others. It is no surprise that a second edition has proved necessary so soon after the first and I welcome the new edition in the confidence that it will prove as valuable to readers as did its predecessor.