In September 2018, a series of earthquakes struck central Sulawesi province triggering a tsunami that hit the provincial capital Palu and the coastal city of Donggala with waves up to six meters high. The earthquake, tsunami, aftershocks and resulting liquefaction and landslides caused significant damage, loss of life and challenges for the delivery of aid in the worst affected areas. Since the onset of the disaster, REACH supported response actors by assessing the scale of the damage through remote sensing. The rapid deployment soon developed to a humanitarian needs and shelter assessment of disaster-affected areas.