Abstract
A growing number of binary and tertiary van der Waals and hydrogen-bonded complexes are being studied by means of near-infrared laser spectroscopy. Studies of this type have generated a wealth of detailed structural and dynamical information that provides exacting tests of the corresponding theoretical methods. An additional incentive for the investigation of such clusters arises from the fact that they may be considered as intermediates between the gas and condensed phases of matter. As a result, these systems represent a fertile meeting ground for researchers from both fields and can often be studied with a variety of methods.