As architects, designers, builders, and community advocates, we value the adaptive reuse of buildings, but lack data to verify our design choices. We often operate on intuition to choose what to reuse and what to upgrade, attempting to balance life cycle impacts of new construction materials while lowering operational energy use. Over the last decade, Boston firms Bruner/Cott and Goody Clancy have evolved their practices in high-performance and transformative reuse to think more deeply about the embodied and operational impacts of reuse projects. We’ll look back at four projects’ design strategies for life cycle impact reduction and present retrospective life cycles. These re-assessments will help gauge successes and shortcomings and inform our collective intuition.