The 1991 Active Materials and Adaptive Structures Conference was held to address the explosion in both theory and application of recent and ongoing developments in smart, intelligent, or adaptive structures. The many areas of intelligent systems and smart structures incorporating active materials are now emerging to include major areas of research and development. These include fiber-optic based devices; ferroelectric, shape memory, and electro-rheological- based sensors and actuators; hybrid composites incorporating inherent sensing and actuation; biomimetics; micromachines; adaptive optics; and many others. A wide variety of approaches to sensing and actuation are discussed that exploit the many recent developments in active materials. Such research and development activities are currently taking place in universities, industry, and government laboratories-all of which were substantially represented at the AMAS meeting. Many possible applications of these technologies are described that include already emerging applications in underwater vehicle technology, aircraft systems, smart munitions, civil engineering, biomedical, robotics, and space platforms. These technologies offer the potential of substantial advances in areas such as precision structures, damage assessment/health monitoring, adaptive optics, advanced avionics, and adaptive space structures ensuring both enhanced and more reliable systems.