Software support for the automotive electrical design process is vital, as many of the safety analysis tasks needing to be carried out, while complex, are repetitive and time consuming. Such support is required throughout the design process, but the available commercial tools are only appropriate at specific points in the design process-providing either an early rough analysis or a late but detailed analysis. This paper describes how the capability and utility of safety analysis software can be improved through separating the types of knowledge used into layers. This allows the maximum amount of information to be reused as the design evolves, and enables software tools to track the consequences of changes to the design so that the repercussions of any design change can be understood. The software capability described has profound implications for the design process. Previously, engineers performed a snapshot design safety analysis at some point in the design process, even if they had an automated design safety analysis tool to assist them. The process and tool arrangement described in this paper enables engineers to continually monitor the status of a design, noting the implications of any changes or refinements to the design.