This volume contains the proceedings of the NATO-Advanced Study Institute on the "Spectroscopy of Biological Molecules", which took place on July 4-15, 1983 in Acquafredda di Maratea, Italy. The institute concentrated on three main subiects: the structure and dymanics of DNA, proteins, and visual and plant pigments. Its timeliness has been linked to rapid advances in certain spectroscopic techniques which yielded a consider able amount of new information on the structure and inter actions of biologically important molecules. Among these techniques Fourier transform infrared, resonance and surface enhanced 'Raman spectroscopies, Raman microscopy and micro probing, time resolved techniques, two photon and ultrafast electronic, and C-13, N-15 and P-31 NMR spectroscopies and kinetic and static IR difference spectroscopy receiced a great deal of attention at the Institute. In addition, an entirely new technique, near-millimeter-wave spectroscopy has been presented and discussed. Two introductory quantum chemical lectures, one on the structure of water in DNA, and another pn the energy bands in DNA and proteins set the stage for the experimentally oriented lectures that followed. Fundamental knowledge on hydrogen bonding was the topic of two other lectures. Panel discussions were held on the structure and confor mations of DNA, metal-DNA adducts and proteins and on visual pigments. Many scientists who normally attend different conferences and never meet, met at Aquafredda di Maratea. We feel, that at the end of our Institute a synthetic vi~w emerged on the powerful spectroscopic and theoretical methods which are now available for the study of biological molecules.