Sustainability in technology is often discussed at a high level, but far less attention is given to what it actually means in practice for the teams designing, building and running modern systems. This session brings the conversation back down to reality. Where do emissions really come from in software? How much is driven by cloud infrastructure, compute intensity, and inefficiencies that are often invisible at scale? And as AI adoption accelerates, how do organisations balance its environmental cost with the value it creates? Rather than taking a theoretical view, this panel focuses on the decisions being made every day inside engineering and product teams. What does “green software” actually look like when you are shipping product? What trade-offs are being made between performance, cost and sustainability? And who is ultimately accountable for those choices? Bringing together perspectives from engineering, sustainability and policy, the discussion will explore how organisations are starting to respond, where progress is real, and where gaps still exist. If sustainability was treated as a core constraint, not a consideration, how differently would we build?