Legacy Systems Older software systems that remain vital to an organisation ©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 26 Slide 1 Objectives To explain what is meant by a legacy system and why these systems are important To introduce common legacy system structures To briefly describe function-oriented design To explain how the value of legacy systems can be assessed ©Ian Sommerville 2000 Software Engineering, 6th edition. Chapter 26