Mark Stefik is a PARC research fellow and currently manages the Human-Machine Collaboration area. He is also principal investigator for PARC’s DARPA-funded Explainable Artificial Intelligence (XAI) project, COGLE (COmmon Ground Learning and Explanation). COGLE’s autonomous agents fly unmanned aircraft systems in a simulated world to perform rescue and delivery missions. The agents learn from their performance using reinforcement learning and can explain their activities using common ground terminology. A goal of the project is to enable people and machines to work and learn collaboratively drawing on their mutual strengths. Previously Mark led the CitySight® project, which built an analytics and workflow recommendation system for urban traffic control and parking organizations. The CitySight project did the ethnography and technical research and built a proof-of-concept demonstration system. When this was well received by Xerox customers, the project morphed. Working with a Xerox engineering team, Xerox marketing and sales, and an external software company, it developed and launched the CitySight product in 2016. The CitySight product now serves several major U.S. cities and is offered and operated by Conduent. Mark’s previous projects include personalized news, sense making systems, hardware and software for collaboration in electronic meetings, object-oriented programming systems, and knowledge systems. Mark contributed to several PARC spinouts. His digital property rights research laid the technical foundations for secure distribution for digital media including music, movies, books, and other things. Mark has over 100 patents and 200 publications. He has authored five books, including Breakthrough: Stories and Strategies for Radical Innovation from The MIT Press. Dr. Stefik’s Ph.D. work at Stanford University was on experiment planning in molecular genetics. He is a Fellow of the American Association for Artificial Intelligence (AAAI) and American Association for the Advancement of Science (AAAS).