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Reviewer: Leo L. Pipino

In the preface to his book, Edward Yourdon poses the question “Does the world really need another book on systems analysis__?__” On reading this book most readers will agree, I believe, that it is a useful addition to the current literature on systems analysis. Novice analysts and students in a systems analysis course are the intended audience. Seasoned professionals, however, will also find portions of the book helpful. The book is organized into five major sections: four parts constitute the main text and the fifth contains a set of appendices. Part 1 introduces basic system concepts, major approaches to the development of information systems, an overview of some major development tools, and an elaboration of issues such as productivity and reliability which should be of concern to analysts. Part 2 presents the tools necessary to perform structured analysis—structured analysis as defined by Yourdon and in the classic books of DeMarco [1] and Gane and Sarson [2]. Not unexpectedly, the tools he reviews are those commonly associated with this approach to systems analysis. Yourdon, however, suggests the use of two additional tools when performing analysis. To the traditional dataflow diagrams, data dictionary, and process specifications, Yourdon advocates adding the entity-relationship (ER) model to represent the database and state transition diagrams to aid in the analysis of real-time systems. A minor deficiency in the exposition of the ER model is the author's use of the older form of ER diagrams instead of the revised form which, for example, introduces the concept and symbol for a composite entity. Part 3 addresses the process of system analysis in detail. Here again Yourdon has modified the traditional structured analysis methodology. He advocates a “middle out” approach introducing the idea of upward leveling of dataflow diagrams along with the traditional downward leveling. New terminology is also introduced. The author writes of the environmental model, the behavioral model, and the user implementation model of the system. The three roughly correspond to the context diagram, the set of leveled dataflow diagrams, and the model of the system with automation boundaries identified and user interfaces defined, respectively. The author uses reasoned justification and interesting historical observations to support his suggestions. The final part of the main text, Part 4, provides a linkage with the process of system design. This part presents summary coverage of design techniques, discusses the issues relating to such topics as programming and testing, and covers maintaining the system's specifications. A set of seven appendices completes the book. The appendices address such diverse topics as automated tools, cost-benefit analysis, guidelines for developing time estimates, and the conduct of walkthroughs and of interviews. They also include two extensive case studies that apply the techniques elaborated in the main text. The placement of these topics in separate appendices makes this important material available to the interested reader without diverting attention from the main thrust of the book. Although the author emphasizes a particular methodology and a set of modeling tools for performing systems analysis, he explicitly takes the position that which tool is used is not as important as the goodness of the tool. By presenting explicit criteria with which to evaluate this goodness, the book serves the student, the novice analyst, and even the experienced practitioner well. Indeed, guidelines for performing specific tasks and for avoiding pitfalls are abundantly interspersed throughout the text. The book is surprisingly free of typographical errors. A number of the incidental illustrations, mostly in Part 1, are somewhat amateurish. The technical diagrams, such as dataflow diagrams and entity-relationship diagrams, are well presented, however. From a teaching perspective, I would like a few more short cases as exercises at the end of some of the tool chapters. In summary, this book is well written and eminently readable. It provides comprehensive coverage of the subject matter. The book meets its objective of providing a current, relevant, and readable text for the novice analyst and serving as a source text for the seasoned practitioner. I would recommend its consideration to those evaluating textbooks for use in a systems analysis course.