Research in cognitive psychology, linguistics, and artificial intelligence - the three disciplines that have the most direct application to an understanding of the mental processes in reading - is presented in this multilevel work, originally published in 1980, that attempts to provide a systematic and scientific basis for understanding and building a comprehensive theory of reading comprehension. The major focus is on understanding the processes involved in the comprehension of written text. Underlying most of the contributions is the assumption that skilled reading comprehension requires a coordination of text with context in a way that goes far beyond simply chaining together the meanings of a string of decoded words. The topics discussed are divided into five general areas: Global Issues; Text Structure; Language, Knowledge of the World, and Inference; Effects of Prior Language Experience; and Comprehension Strategies and Facilitators, and represent a broad base of methodology and data that should be of interest not only to those concerned with the reading process, but also to basic science researchers in psychology, linguistics, artificial intelligence, and related disciplines.