NMR imaging promises to provide useful and unique diagnostic information in a variety of diseases. In an attempt to evaluate its role, we plan to study a wide range of diseases during the initial year of imaging. Exposure to magnetic fields and radiofrequency energies of this magnitude have demonstrated no deleterious effects clinically or in the laboratory. The only restrictions will be those imposed by ferromagnetic objects within the patient which would increase the risk of placing them in a strong magnetic field.