An Integrated Framework for Analysing Changing Requirements Contents 1 Introduction 1 2 Overview of the Goal-based Framework for Requirements Anal- Ysis 2

The problem of analysing the eeects of changing requirements imposes strict demands on system representations, particularly in safety-critical domains. We argue that solving this problem will require structured representations that highlight the interaction between requirements, and record the rationale for decisions made during the development process. As a means of providing and analysing this information, we propose a framework, called goal-structured analysis, that integrates three components: a goal-oriented model for imposing the desired structure on requirements, natural language processing for useability of the system and avoidance of change via the creation of clear speciications, and formal reasoning for performing impact and sensitivity analaysis.