Sunney Xie is one of the world’s leading researchers in molecular imaging and in single-molecule reactions. Xie’s has devised a way to use laser beams to see collections of protein molecules. The new imaging method is important because it allows researchers to see how biomolecules are assembled in biological membranes and how their relative position may affect their behavior. Xie, for example, works with membranes that carry out the process of photosynthesis. By seeing the arrangement of proteins in the photosynthetic membrane, researchers may be better able to determine how the membrane converts sunlight to chemical energy.