This resource sets out DIMPACT’s proposed principles for addressing digital advertising emissions in alignment with content publishers. It highlights advertising’s influence to drive sustainability outcomes, the need for consistent, comparable emissions metrics, and the importance of translating footprint data into genuine decarbonisation rather than shifting emissions. The principles emphasise focusing action where industry players have the greatest influence, using robust first‑party data alongside credible shared estimates, and collaborating across the advertising and media ecosystem to support transparent measurement and meaningful emissions reduction.