Williams went on to thank the studio that produces Fosse/Verdon for "supporting me completely and paying me equally".
"They understood that when you put value into a person, it empowers that person to get in touch with their own inherent value and then where do they put that value? They put it into their work," she said.
"So the next time a woman, and especially a woman of colour, because she stands to make 52 cents on the dollar compared to her white male counterpart, tells you what she needs in order to do her job, listen to her, believe her, because one day she might stand in front of you and say, 'Thank you for allowing her to succeed because of her workplace environment and not in spite of it'."
Jamie Lee Curtis was just one of the many stars who shared Williams' speech on Twitter, with the Halloween actress writing: "That is the best speech ever. Google it. Watch it. Learn from it. My friend Michelle Williams. Wow!"
Another Twitter user commented, "That Michelle Williams speech belongs on a plaque", while journalist Siobhan Morris tweeted, "Every boss everywhere should watch Michelle Williams' #Emmys speech. Hear it, live it."
The issue of equal pay is particularly important to Williams who has previously spoken about being "paralysed in feelings of futility" after discovering she had been paid substantially less than Mark Wahlberg for All The Money In The World.
"When I asked for more dance classes I heard, 'Yes'; more voice lessons, 'Yes'; a different wig, a pair of fake teeth not made of rubber, 'Yes'," Williams said on stage, news.com.au reports.
In late 2017, news broke that Williams had been paid less than $US1000 ($A1409) for 10 days of reshoots on the film. But, in contrast, Wahlberg was paid $US1.5 million ($A2.11 million) for the reshoot.
Speaking to Channel 10's Angela Bishop backstage after winning the Emmy, Williams said the pay gap for All The Money In The World "woke me up".
"I'd always known from the inside how difficult it was to feel like you were ever really getting ahead," Williams said. "It felt like no matter how many accolades I amassed, I still couldn't make that translate into retirement money or something that really felt like long-term security.
"The discrepancy on All The Money In The World was so huge that it really illustrated a larger point, and not just for myself obviously, but as I've said before, if it was this difficult for me, a white woman in a privileged industry, how difficult is it for women of colour across all industries.
"While tonight is a kind of fairytale ending for me and my own personal story, there really won't be any satisfaction for me until the larger message is heard. That's what I really wanted to point out tonight," she said.
