In the state of the art today, there's a yawning gulf between voice user interface research and practice. More recent writings on the subject point to the symbiotic relationship between research and practice: Basic research provides a basis for the design of new products, and practical design stimulates the questions that will advance the knowledge base. Designers should demand the air cover that comes from research when they're in the trenches. If you don't have this background, you need to be persistent about getting it from your company, professional organizations, and industry conferences. Don't be afraid to tell mentors, peers, and managers what you need to design effectively.