Ken Johnston is Principal Data Science Manager for the Microsoft 360 Business Intelligence Graph and the implementation of Differential Privacy technologies on Windows data. He is a frequent keynote presenter, trainer, blogger, and author on software testing and data science. Since joining Microsoft in 1998 Johnston has shipped many products, including Commerce Server, Office 365, Bing Local and Segments, and Windows. For two and a half years he served as the Microsoft director of test excellence. He earned his MBA from the University of Washington, is a coauthor of How We Test Software at Microsoft, and is a contributing author to Experiences of Test Automation: Case Studies of Software Test Automation.