This chapter reviews two recent technologies that may be used to mitigate urban overheating—transpiration cooling and quantum dots (QDs) coating. The first part of the chapter discusses the transpiration of plants and the cooling effect of transpiration. For decades, a large number of studies have shown that plants in cities can effectively alleviate urban overheating problems. The cooling effect of plants mainly comes from shading and transpiration effects. The first part of the chapter reviews the principle of transpiration and its influencing factors. Then, the cooling potential of transpiration and the interaction between urban vegetation and extreme climates are discussed. The second part of the chapter reviews the urban overheating mitigation potential of advanced heat-rejecting fluorescent materials or so-called quantum dots (QDs). Unlike conventional cool coatings relying on high near-infrared reflection values as their heat rejection method, fluorescent materials reject the incident light through reemission of the absorbed visible-range light. The distinguishing feature of QDs compared to their bulk counterparts is their adjustable fluorescent property feature. Also, QDs present high light permeability in the near-infrared range, which makes the combination of fluorescent and near-infrared (NIR)-cooling methods possible through a two-layered coating system.