This volume is based on a series of lectures delivered at a one-day teach­ ing symposium on functional and metabolic aspects of NMR measure­ ments held at the Middlesex Hospital Medical School on 1st September 1985 as a part of the European Nuclear Medicine Society Congress. Currently the major emphasis in medical NMR in vivo is on its poten­ tial to image and display abnormalities in conventional radiological im­ ages, providing increased contrast between normal and abnormal tissue, improved definition of vasculature, and possibly an increased potential for differential diagnosis. Although these areas are undeniably of major importance, it is probable that NMR will continue to