Mark Klein is Senior Member of the Technical Staff at the Software Engineering Institute and is Technical Director of its Critical System Capabilities Directorate, which conducts research in cyber-physical systems and advanced mobile systems. His research has spanned various facets of software engineering, dependable real-time systems, and numerical methods. Klein’s most recent work focuses on design and analysis principles for systems at scale, including cyber-physical systems. He is co-author of many papers and three books: Ultra-Large-Scale Systems (Software Engineering Institute/Carnegie Mellon, 2006), Evaluating Software Architectures (Addison-Wesley, 2001), and A Practitioner’s Handbook for Real-Time Analysis< (Springer, 1993).