Peak Reliability (Peak) and eight of its member transmission organizations deployed synchrophasor technology throughout the U.S. portion of the Western Interconnection. The project installed or upgraded 584 phasor measurement units (PMUs) (393 using WISP program funding), 77 phasor data concentrators (PDCs) (57 using WISP program funding), a wide-area communications network to support PMU data transfer, information technology infrastructure, and advanced transmission software. Together, these systems increase grid operators’ visibility into bulk power system conditions in near-real time, enable earlier detection of problems that threaten grid stability or cause cascading outages, and facilitate sharing of information with neighboring control areas.