© 1991 SPIE. All rights reserved. The newly commissioned Vanderbilt Free Electron Laser Center for Biomedical and Materials Research is a multidisciplinary users facility intended as an international resource. It provides extremely intense, continuously tunable, pulsed radiation in the mid-infrared (2-10 j.tm). Projects already underway include the linear and nonlinear interaction of laser radiation with optical materials, semiconductors, and mammalian tissue, the spectroscopy of species adsorbed on surfaces, measurement of vibrational energy transfer in DNA and RNA, the dynamics of proteins in cell membranes, the biomodulation of wound healing by lasers, image-guided stereotactic neurosurgery, and the use of monochromatic X-rays in medical imaging and therapy. The purpose of this article is to introduce the machine to the user community and to describe some of the new experimental opportunities that it makes possible. Details of several research projects are presented.