This volume contains the invited papers presented at the NATO Advanced Research Workshop on "Stochasticity and Intramolecular Redistribution of Energy" held in Orsay (France) from June 23 to July 3, 1986. The Work­ shop brought together leading researchers involved in the experimental and the theoretical studies of vibrational energy flow and relaxation in activated polyatomic molecules. The recent experimental developments in this area include the study of ultracold molecules in supersonic beams and the development of high resolution (frequency domain) and ultrafast (time domain) spectroscopic techniques. On the theoretical side the intro­ duction of statistical methods (random matrix theory, reduced equations of motion) and efficient numerical algorithms provide an adequate frame­ work for the interpretation of vibrational dynamics in large polyatomic molecules. Classical, semiclassical and quantum calculations on simple model systems show the existence of regular and chaotic regions in the phase space. The articles in this volume provide an updated review of the current status of experimental studies and the relevance of the recent theoretical developments to their interpretation. We wish to thank the organizations which made this workshop possible. NATO prov ided the basic grant. We acknowledge the essential contribu­ tion of the late Dr Mario di Lullo in providing pertinent advice. The gen­ erous support of the U. S. Air Force Office of Scientific Research, the U. S.