You know your hashtag has gone viral when one of the most powerful women in business tweets it to her 15,000 followers. Mary Barra, the CEO of American auto manufacturing giant General Motors wrote the following yesterday:
Barra studied electrical engineering at General Motors Institute (now Kettering University), obtaining a Bachelor of Science degree. She started working for General Motors at the age of 18 as a co-op student in 1980 and subsequently held a variety of engineering positions, though she later became the VP of Global Human Resources despite her concerns that "it didn’t fit [her] engineering and manufacturing credentials."
The #ILookLikeAnEngineer hashtag began circulating in the Twitter-sphere after Isis Wenger, a developer at San Francisco-based OneLogin, was featured in a prominent ad in the city's transport system, BART.
The ad sparked a slew of negative and sexist comments, implying that Wenger could not possible be an engineer because of her looks. Those comments inspired a Medium post, in which Wenger asked the online community to spread awareness about gender diversity in engineering and tech:
Do you feel passionately about helping spread awareness about tech gender diversity?
Do you not fit the “cookie-cutter mold” of what people believe engineers “should look like?”
If you answered yes to any of these questions I invite you to help spread the word and help us redefine “what an engineer should look like”.#ILookLikeAnEngineer
To-date, over 36,000 women have answered her call, with Barra one of the most prominent among them. But the movement looks like it's only gaining more and more momentum. Now where are all the other powerful female engingeers? Looking at you, Ginni Rometty, Ursula Burns, and Marissa Mayer.
Subscribe to The Broadsheet, Fortune’s daily newsletter on the world’s most powerful women.