American Transmission Company’s (ATC) Phasor Measurement Unit Project is deploying synchrophasor technologies across the company’s Wisconsin service area. The project expands the collection of synchrophasor data throughout ATC’s transmission system from 25 substations to 73 substations by project completion. ATC is using synchrophasor monitoring to improve electric system reliability and restoration procedures and to help prevent the spread of local outages to neighboring regions. The project deploys phasor measurement units (PMUs), digital fault recorders (DFRs), a new synchrophasor data concentrator, and improved data collection software. These devices increase the ability of grid operators to monitor the condition of bulk power systems in near-real time, enable earlier detection of conditions that could result in grid instability or outages, and facilitate the sharing of information with neighboring regional control areas.