Causal analysis of the requirements change process for a large system

Implementations of requirements change processes in large system projects face many difficulties. In this paper we present a method for analysing requirements change processes to identify implementation weaknesses and their causes. This method relies on prescriptive process models and tracing actual Change Proposals through the process model. We apply the method in the analysis of the requirements change process for a large real-time system within a Canadian government agency. This allowed us to identify the process implementation problems, and the process, organisational, and people causes of these problems. Based on that experience, we draw general conclusions about the proposed method and its applicability.