This book reports recent research on mechanisms of normal formulation and control in speaking and in language disorders such as stuttering, aphasia, and verbal dyspraxia. The theoretical claim is that such disorders result from (1) deficits in a component of the language production system and (2) interactions between this component and the system that "monitors" for errors and undertakes corrective behavior. More in particular, the book focuses on phonological encoding in speech (the construction of a phonetic plan for the utterance), on verbal self-monitoring (checking for correctness and initiating corrective action if necessary), and on interactions between these processes. The first part of the book deals with phonological encoding. The architecture of the phonological encoding system is described, with regard to both normal and patholgical (conduction aphasia, stuttering, developmental dyspraxia) production. Both in normal and in pathological speech, there are monitoring processes that control speech. These control mechanisms for detecting and correcting these errors are discussed. The second part of the book outlines the architecture of monitoring, both from an empirical and a modelling approach. subsquent chapters deal with language dysfunction, either as a disturbance in monitoring itself or as the result of interactions between monitoring and phonologiclal encoding.