The motivation for this volume came about in late 1989 when the editors were putting together a research proposal concerned with input. We realized that, in spite of the dramatic increase of studies in this area, there were few survey articles covering the most recent developments. Above all, no single source existed to which we could conveniently refer which would set out the complex arguments now surrounding input issues and which also included important new directions appearing in the late 1980s. In particular, we noticed that no attempt had been made to produce a sequel, as it were, to Snow and Ferguson (1977).

Our aim in producing this book, therefore, has been twofold: firstly, to provide a survey of both classical and recent input and interaction studies, including studies concerning particular types of learner and particular types of context in which language is acquired; and secondly, to provide a detailed assessment of the theoretical issues and controversies in the area. We believed that this daunting task would be best tackled by sharing it with others directly involved in the field.

The book is organized as follows: the scene is set by the Introduction, in which the development of the research area over the years is described, the main body of text consists of chapters on specific issues grouped into three broad areas, and a synthesis of the findings and general implications of the research can be found in the final chapter.