Co-evolution of complementary formal and informal requirements

Agent-oriented Conceptual Modelling (AoCM, as exemplified by the i* notation [5], represents an interesting approach to modelling early phase requirements that is particularly effective in capturing organizational contexts, stakeholder intentions and rationale. There are significant benefits in using formal methods for the development of computer systems and improving their quality. We propose a methodology which permits the use of these two otherwise disparate approaches in a complementary and synergistic fashion for requirements engineering.