Analysis within the Systems Development Life-Cycle: Book 4, Activity Analysis—The Methods describes the techniques and concepts for carrying out activity analysis within the systems development life-cycle. Reference is made to the deliverables of data analysis and more than one method of analysis, each a viable alternative to the other, are discussed. The ""bottom-up"" and ""top-down"" methods are highlighted. Comprised of seven chapters, this book illustrates how dependent data and activities are on each other. This point is especially brought home when the task of inventing new business activities is discussed, and the data model is changed with completely new entity types—the invention of the user and analyst being added—and ""old"" entity types being removed when the activities of the business are changed. The relevance of PROLOG, LISP, knowledge bases, and expert systems is considered, and these areas of interest are brought together into the fold of ""conventional"" systems development. Finally, this text shows how the ""rules"" of the knowledge base and the ""deduction"" clauses are directly related to the activity concepts. This monograph will be a valuable resource for systems analysts and designers and those who are involved in expert systems.