Introduced as "the woman who put this entire evening together", Gaga opened the show by extending thanks to healthcare workers on the front lines, to Global Citizen and World Health Organization, and with a message for viewers at home.
We have rounded up the ways you can see the show or live stream it below.
Whereas the special will not be a public fundraiser, it is usually geared toward encouraging philanthropists and corporations to contribute to the WHO's COVID-19 Solidarity Response Fund. Company and different donors have already contributed some $35 million, organizers mentioned final week.
Global Citizen has put together a resource page detailing how to watch the special for viewers across Africa, Asia, Australia, Europe, North America, and South America.
The two-hour broadcast also included stories from frontline workers in the U.K. Additional footage from the main concert will be available on catch-up service BBC iPlayer for 30 days.
Before coming up with the performance, Beatles' "Lady Madonna" alongside footage of healthcare workers, he made a plea: "Let's tell our leaders we need to strengthen the health care system around the world so that a crisis like this never happens again".
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Im honored to have been a part of One World #TogetherAtHome last night.
$50 million had been raised by corporations in advance, to help support the World Health Organization's work.
Swift, on piano, gave an emotional rendition of her ballad "Soon You'll Get Better", which was originally written during her mother's battle with cancer.
"One World: Together At Home" demonstrated unity among all people who are affected by COVID-19 to celebrate and support courageous healthcare workers doing life-saving work on the frontlines.
John sang his powerful I'm Still Standing, country star Kacey Musgraves sang Rainbow and Canadian duo Mendes and Cabello performed Louis Armstrong's What a Wonderful World.
She went on to play an upbeat version of Charlie Chaplin's Smile, adding: "We want to get to the other side of this pandemic and we know you do too".
Former First Ladies Laura Bush and Michelle Obama teamed up for a hopeful message amid the bleakness of the crisis.