A comprehensive survey of current research and development in the area of spoken dialogue technology is presented in this paper. Included as components of that technology are speech recognition; language understanding; dialogue management; communication with external sources, such as databases; language generation; and speech synthesis. The paper emphasizes recent advances both within spoken dialogue technology and in underlying computer technology. There is a focus on surveying underlying technologies rather than existing spoken dialogue systems.

Section 1 of the paper gives an overview and an introduction to the subject. Section 2 is used to define the subject and to set forth a classification system. Three examples are given in section 3 to illustrate control strategies used in spoken dialogue systems. In section 4, there is an overview of the components used in spoken dialogue systems. It is noted that spoken dialogue systems are complicated systems that need to integrate these components, where each component itself is a major area of research interest. Section 5 describes methods of dialogue control. Section 6 reviews current trends in the specification, design, and evaluation of spoken dialogue systems. Section 7 describes toolkits that can be used in developing these complex systems. Finally, section 8 discusses future directions. The paper also includes a comprehensive list of related Web sites, and an extensive reference list.

The technology surveyed is important and interesting. The paper itself is well organized and clearly written. This work should be invaluable to anyone with an interest in spoken dialogue systems.