Around 30% of Earth’s land surface is covered by forest. It is estimated that this precious forest is home to around 80% of biodiversity on land. The Biomass mission will measure forest biomass, height and disturbance to address gaps in our knowledge of the carbon cycle. It will deliver data with the resolution and accuracy needed for international reporting on carbon stocks and terrestrial carbon models. Biomass’ observations will also lead to better insight into rates of habitat loss, and the impact this may be having on biodiversity in the forest environment.