Stephen J. Pennycook is a professor in the department of materials science and engineering, University of Tennessee, and the department of materials science and engineering, North Carolina State University. Previously, he was corporate fellow in the Materials Science and Technology Division of Oak Ridge National Laboratory and leader of the Scanning Transmission Electron Microscopy Group. He received his Ph.D. in physics from the Cavendish Laboratory, University of Cambridge, in 1978. Pennycook is a Fellow of the American Physical Society, the American Association for the Advancement of Science, the Microscopy Society of America, the Institute of Physics and the Materials Research Society, and is recipient of the Microbeam Analysis Society Heinrich Award, the Materials Research Society Medal, the Institute of Physics Thomas J. Young Medal and Award and the Materials Research Society Innovation in Characterization Award. He has 38 books and book chapters, over 400 publications in refereed journals and has given over 200 invited presentations on the development and application of atomic resolution Z-contrast microscopy and electron energy loss spectroscopy.