The focus of software engineering is moving from writing reliable large-scale software to ensuring that this software meets the needs of the users for whom it was designed. The business of eliciting and then implementing the (often changing) user requirements is requirements engineering. This book is intended for the undergraduate novice who is being introduced to software requirements engineering. It is a hard subject for which there is no formulaic approach and for which it is sometimes difficult to motivate students who are unaware of the problems involved and therefore the need to study the subject. It therefore begins with small, relatively simple, case studies and builds on these to provide the opportunities to scale up this expertise to large industrial projects. The book will be in three parts: the first provides a guide to all the important requirements engineering toppics; the second gives more detail on useful techniques (for problem definition and modelling); the third contain the complete case studies, extracts from which are used in parts one and two. Requirements Engineering is a jargon-filled subject, so a comprehensive glossary is provided as well as definitions within the text.