This introductory chapter sketches an overview of the origins of and background to the constrained language (or constrained communication) framework that informs this volume. It outlines the five constraint dimensions identified in the framework, and the usage-based theoretical grounding of the framework. Subsequently, each chapter in the volume is situated within the framework, highlighting how each study contributes to the further development of the framework. The chapter concludes with some brief reflections on methodological challenges for the study of constrained language.