Amidst political decision-makers and leading scientist from around the world, 3CSEP director Diana Ürge-Vorsatz and two junior researchers are present at the COP15 climate summit in Copenhagen. On December 11, 2009, Prof. Ürge-Vorsatz contributed to "Construction Counts for Climate", a COP15 side event on low carbon policies for buildings and construction - a sector offering huge potential for carbon mitigation, given that almost 40 percent of all energy is consumed in buildings.