[en] The Chalk River Symposium on Inelastic Scattering of Neutrons in Solids and Liquids was the International Atomic Energy Agency's second symposium held on this subject. The previous one was held in 1960 in Vienna and the very first international meeting in this field took place in 1957 in Stockholm. At the Stockholm meeting only 11 papers from six countries were presented; this was the very beginning of a rapidly developing new branch of physics. At the Vienna Symposium there were 50 papers from 12 countries. At Chalk River 67 papers from 13 countries and three international organizations, the European Atomic Energy Community, the Joint Institute for Nuclear Research and the International Atomic Energy Agency, were presented and discussed. In several other countries, either research in this field has already begun or preparations to start it are under way. This is an indication that the interest in using inelastic scattering of neutrons as a method to study the internal dynamics of solids, liquids and molecules is continuously increasing. On the other hand, a deeper knowledge of the dynamic properties of moderators plays an important role in the understanding of the process of thermalization of neutrons. The latter study is of special importance in promoting advances in nuclear reactor technology. In the light of these developments the International Atomic Energy Agency, with the co-sponsorship of the United Nations Educational, Scientific and Cultural Organization, organized the Symposium at Chalk River from 10 to 14 September 1962 on the generous invitation of the Government of Canada and Atomic Energy of Canada Limited.