The small-scale dynamic model is a powerful tool for understanding structural behavior where analytical techniques are inadequate. Eleven papers are presented in this volume, beginning with similitude requirements and dynamic properties of model materials. Four papers are included on seismic loading of frame structures, frame-wall structures, arch dams, and long-span bridges. Other topics include air-blast loading of buried structures; impact loadings on beam-to-column joints and on reinforced concrete slabs; and vibration studies of both floor slabs and large panel buildings.