Safety analysis is essential for high-assurance software systems. Safety analysis identifies the hazards, derives the software safety requirements to eliminate or control these hazards, and ensures that the design and implementation incorporate those safeguards. A product line is a set of products that share a common set of features and a related market or mission.Currently, high-assurance product lines are being built without the tools or conceptual framework necessary to perform effective safety analyses. This research addresses the question of how safety analysis can become a reusable asset of a product line by developing a framework and asuite of techniques for the safety analysis of critical product lines. Anticipated benefits of the research include extending safety analyses toproduct lines, providing a framework for reuse of safety analyses within a product line, deriving formally specified limits on reuse of product-line safety analysis, and enabling safer product-line systems at lower cost and reduced schedules. The results will be empirically evaluated by application in industrial case studies. This project will expand the opportunities available to student researchers to participate in development of safety-analysis techniques for product lines.