This Advanced Study Institute was held at -lellesley College, Wellesley, MA., from 3 to 12 August 1980. It followed by four years the second "Capri, chool on Photon Correlation Spectroscopy." During the intervening period there had been many new applications of dynamic light scattering techniques to the study of systems whose properties depend either on collective molecular interactions or on the formation or activity of supramo1ecu1ar structures. Con- sequently, emphasis at this conference was on light scattering studies of subjects such as dynamical correlations in dense polymer solutions,...