Being able to understand your impact on the world and how to measure it is becoming increasingly important. But we found it is also complex: there is no shared understanding in the cultural heritage community of what impact is or how to assess it at the moment. We want to use this space to share ideas and discuss what impact means to the sector. [Image credit: Workers Underground, Anonymous 1914–1920, Europeana 1914–1918 CC BY-SA]