This introductory text gives the student a general appreciation of the phases involved in the development of effective software. It enables the student to analyse a set of initial user requirements into four major categories and to be aware of the role played by each category in software development; to use one major technique for further detailed analysis of user requirements and employ three notations for recording the results of the analysis. The user will ultimately be able to compile a detailed specification of requirements to enable the design of the new software to commence. The text introduces the Software Engineering Life Cycle,and goes on to include detailed sections on Requirements,Specification and Design. It is based on Open University course units and thus contains a high degree of pedagogy and tutorial material.