Digital nudging leverages behavioral science and information technology to provide a new set of tools for designers to change behavior and create habits. Examples of digital nudges include smart feedback and reminders and technology defaults. In this chapter, I discuss the role of design and data in digital nudging and applications in the domains of consumer choices, health behavior, and daily work. To help expand research and practice, I propose three principles for the design of digital nudging solutions: choice of technology, use of data, and digital experimentation.