If you work in computer science, or recently graduated from an elite university, or read Vox’s Future Perfect section, or find yourself drawn to certain “highly rational” corners of the internet, there’s a good chance you’ve already come across effective altruism.

Now more than a decade old, EA—as it has been known since 2011—is a philosophy, a social movement, and, increasingly, a way of life. And it’s thriving. EA started in 2007 with GiveWell, a rigorous charity assessment tool. In 2011, the Centre for Effective Altruism was formed in the UK to give the movement structure and direction. EA raises billions for recommended charities and causes, as well as through its own philanthropic funds.

Effective altruists congregate the world over with nearly 400 global chapters, often connected to high-ranking universities or tech centers. Their numbers encompass at least two Giving Pledge signees, including Facebook co-founder Dustin Moskovitz, whose assets exceed $10 billion, as well as dozens of other high-profile donors. Arguably, no other secular movement ever has had as much impact in changing how people think about their philanthropic responsibility.