Abstract

A legacy system is made up of technical components and social factors (such as software, people, skills, business processes) which no longer meet the needs of the business environment. The study of legacy systems has tended to be biased towards a software engineering perspective and to concentrate on technical properties. This paper suggests that the evaluation of potential change options for legacy systems can only be carried out as part of an holistic organisational analysis. That is, the evaluation of legacy systems must take place within a framework that combines business and technical considerations. In particular, we believe that the business strategy must lead this process. Accordingly, we have designed an inter-disciplinary approach which brings together an organisational scenarios tool (based on concepts from the field of organisational development) and a technical scenarios tool (based on concepts from the field of software engineering). These tools are applied in an iterative way, so that technical options are tested out against the business needs. It is, thus, a dynamic tool which seeks to mimic the nature of organisational change, as far as is practicable. The research project described here is entitled software as a business asset (SABA) and was funded by the Engineering and Physical Sciences Research Council (EPSRC) under the systems engineering for business process change (SEBPC) programme. This paper describes the research approach and its iterative stages, and illustrates its use within a large engineering firm (Engco). Its application produced useful insights for the organisation, as well as pointers for further modification of our research approach