The built environment is increasingly shifting from a focus on “less harm” toward regenerative design - where buildings actively contribute to the health of people, ecosystems, and material cycles. This is the second in a three-part Lean In series focused on assessing sustainable materials and embedding regenerative design as part of projects and in everyday practice. The overarching series explores the role of material specification, research and design considerations that enable this shift. In Part 2 of this Lean In series we explore how architects and designers can evaluate, compare, and measure materials and building systems in the design process. We hear from Lucy Marsland (Atelier Ten) and Adam Kolsrud (Wardle) on how sustainability value systems have been embedded in their practice and the considerations, tools and methods for assessing upfront carbon in materials and building systems on projects. Each session will prioritise practical insights and clear takeaways, enabling participants to apply learning directly to their projects and practice and to consider ‘What should I do differently on Monday morning?’.