Arjun Yodh is the James M. Skinner Professor of Science in the Department of Physics and Astronomy at the University of Pennsylvania. His biomedical research is oriented toward imaging and monitoring with diffusing light; this research explores fundamental aspects of light transport and aims to demonstrate the potential of these tools for functional imaging/monitoring in brain, breast, and muscle. He also directs the Laboratory for Research on the Structure of Matter, an interdisciplinary materials institute that hosts the Penn NSF-MRSEC.