Practical speech user interface design Although speech is the most natural form of communication between humans using speech to communicate with machines is anything but natural. Drawing from psychology human computer interaction linguistics and communication theory this book provides a comprehensive yet concise survey of practical speech user interface design. The text presents research and practice based guidance for the development of usable speech user interfaces such as the interactive voice response applications designed to provide phone based call routing and self service. The author a leading human factors engineer covers both high and low level decisions and also includes VoiceXML code examples