This book provides a new multi-method, process-oriented approach towards speech quality assessment, which allows readers to examine the influence of speech transmission quality on a variety of perceptual and cognitive processes in human listeners. Fundamental concepts and methodologies surrounding the topic of process-oriented quality assessment are introduced and discussed. The book further describes a functional process model of human quality perception, which theoretically integrates results obtained in three experimental studies. This book's conceptual ideas, empirical findings, and theoretical interpretations should be of particular interest to researchers working in the fields of Quality and Usability Engineering, Audio Engineering, Psychoacoustics, Audiology, and Psychophysiology.