About two years ago, while studying the dynamic properties of Fe (CO)IJ ,we realized that there 3 was virtually no single source of infonnation on the structural dynamics of materials. The time domain of different dynamic structural processes covers many orders of magnitude and may be in­ vestigated by numerous, vastly different, experimental techniques. Indeed, the subject seemed ap­ propriate for a NATO Advanced Study Institute at which we could bring together chemists, physicists, metallurgists, and bioscientists using the various techniques for the study of sundry time sensitive materials. The actual Advanced Study Institute, which met in II Ciocco, Italy, from 14 to 26 June 1987, was, in fact, a dynamic experience for those of us involved. Now we have come to the final phase, the communication of the results of this Advanced Study Institute to the general scientific community. In so doing, we hope to provide in one place a convenient source of infor­ mation on dynamics at the surface and within a solid state material. The beautiful mountainous setting of Tuscany and especially the idyllic surroundings of II Ciocco provided an ideal venue for the Advanced Study Institute. Our field trip to Pisa linked our topic to the history of time measurement through a visit to the Pisa cathedral where, presumably, Galileo first conceived the isochronism of the simple pendulum and its use in time measurement.