Published 100 years after Emil Fischer first proposed the lock-and-key principle, this volume provides a complete review of the subject to date and offers suggestions for futher research. The major impact of the lock-and-key principle on the chemical, biomedical and materials sciences is discussed by leaders in the field, with chapters dedicated to molecular recognition, nucleic acid and protein chemistry, crystallography and the development of Emil Fischer's initial ideas. The Lock-and-Key Principle is the most up-to-date review of progress in supramolecular chemistry and the lock-and-key principle and will become the essential guide to the past, present and future of this remarkable principle.