Cyber-physical systems (CPS) can be described as smart systems that encompass computational and physical components - seamlessly integrated and closely interacting to sense and respond to the changing state of the real world. The Smart Grid is considered an example of a cyber-physical system. NIST performs vital research addressing many of the critical elements that make up the Smart Grid. A critical part of this research portfolio is implemented in a newly constructed Smart Grid 2017 Innovative Smart Grid Technologies Conference (ISGT) 23 - 26 April 2017 Interoperability Testbed. The Smart Grid Interoperability Testbed facility creates a unique set of interconnected and interacting labs in several key measurement areas that will accelerate the development of Smart Grid interoperability standards by providing a combined testbed platform for system measurements, characterization of smart grid protocols, and validation of smart grid standards, all organized around the microgrid concept. In this Panel Session NIST CPS leadership discuss research activities at the Smart Grid Interoperability Testbed.