Book excerpt: A glossary, also known as a vocabulary or clavis, is an alphabetical list of terms in a particular domain of knowledge with the definitions for those terms. In a general sense, a glossary contains explanations of concepts relevant to a certain field of study or action. In this book, all the terms used in healthcare quality improvement, patient safety and risk management used are elaborated with appropriate references and definitions for the students, researchers and professionals. This text book is a purely based on the several national and international healthcare accreditation standards in healthcare service.