Mark Ellisman is a neuroscientist who directs the National Center for Microscopy and Imaging Research (NCMIR), an internationally acclaimed technology development center and research resource. He is a pioneer in the development of 3D light and electron microscopy and emphasizes application of these imaging strategies to the study of brains and the many types of cells which form nervous systems. He partnered with Roger Y. Tsien for nearly 30 years, developing new probe technologies for correlated light and electron microscopy. Current efforts include new probe, instrument and technique development for multiscale and multimodal imaging - all at the frontiers of microscopy, computer science and computational biology.