First, to provide a real-world experimental platform this error handling research program, we developed RavenClaw, a plan-based dialog management framework for task-oriented domains. The framework has a modular architecture that decouples the error handling mechanisms from the do main-specific dialog control logic; in the process, it lessens system authoring effort, promotes portability and reusability, and ensures consistency in error handling behaviors both within and across domains. To date, RavenClaw has been used to develop and successfully deploy a number of spoken dialog systems spanning different domains an interaction types. Together with these systems, RavenClaw provides the infrastructure for the error handling work described in this dissertation. 
