Learning, Speech and Thought in the Mentally Retarded contains the proceedings of Symposia 4 and 5 held at the Middlesex Hospital Medical School in London on October 31, 1969 and March 20, 1970, respectively, under the auspices of the Institute for Research into Mental Retardation. This monograph presents topical problems in mental retardation, with emphasis on learning processes, speech, and thought. The application of operant learning techniques to the development of language in the retarded is highlighted. This book is comprised of four chapters and begins by outlining directions in research on learning deficits, followed by a discussion on teaching processes in the care of severely retarded children. The next chapter deals with speech and thought in the mentally retarded, with particular reference to two basic problems: the relative priority of language or thought and the selection processes underlying language. The final chapter explores language delay and language deviation in mentally retarded children. Throughout the book, the focus is on language: its nature, its development in the constitutionally normal and handicapped, some theoretical controversies among experts in this field, and the development of appropriate techniques for teaching language to the mentally retarded. This monograph will be useful to psychologists and clinicians working in the field of mental retardation.