Acquiring COTS software selection requirements

An increasing number of organisations are procuring off-the-shelf systems from commercial suppliers. However, successful selection of off-the-shelf systems to fit customer requirements remains problematic. The London Ambulance Service fiasco in 1992 is a well-known example of system failure due, at least in part, to poor product selection. New methods and techniques for requirements acquisition and product selection are needed. The authors propose a new method which integrates techniques from several disciplines in response to lessons learned from a complex commercial off-the-shelf product selection exercise undertaken by the authors. They report on a recent experience in selecting a complex commercial off-the-shelf software system to be compliant with over 130 customer requirements, and lessons learned from the experience. These lessons learned inform design of PORE (Procurement-Oriented Requirements Engineering), a template-based method for requirements acquisition. This paper reports 11 of these lessons. Particular focus is put on the typical problems which arose during acquisition of requirements to enable this selection, and solutions to avoid these problems in the future.