In any software project the analysis stage - documenting and designing requirements to meet the needs of the prospective users - is vital to the success of the project. This book provides a thorough introduction to analysis and where it fits into the software engineering process. The author applies his many years of experience both as a manager of software projects and as a consultant to numerous companies to illustrate succesful techniques and to identify potential pitfalls. The book is based on courses offered at Columbia University to a diverse audience of students and professionals. Throughout, the author is concerned to emphasize the stages of analysis and to identify many alternative modelling tools that an analyst can use. Particular emphasis is placed on Joint Application Development and on prototyping. Readers are assumed to have a reasonable understanding of computer concepts and terminology, and so this will be suitable for a first-level analysis course or it can be used by information systems professionals who need an in-depth understanding of the principles of the analysis and design process.