The dynamic response of materials is important to the performance and failure resistance of many engineered systems. Experimental methods are now available to measure this response over a wide range of strain rates and temperatures. Application of these methods to the investigation of the dynamic response of metals, glasses and ceramics has led to important advances in understanding, while bringing into focus important issues that remain to be resolved. In this paper, a number of these issues are discussed and potentially fruitful research directions are suggested. (C) 1999 Published by Elsevier Science Ltd. All rights reserved.