Magic Mushrooms. LSD. Ketamine. The Drugs That Power Silicon Valley.

Elon Musk takes ketamine. Sergey Brin sometimes enjoys magic mushrooms. Executives at venture-capital firm Founders Fund, known for its investments in SpaceX and Facebook, have thrown parties that include psychedelics.

Routine drug use has moved from an after-hours activity squarely into corporate culture, leaving boards and business leaders to wrestle with their responsibilities for a workforce that frequently uses. At the vanguard are tech executives and employees who see psychedelics and similar substances, among them psilocybin, ketamine and LSD, as gateways to business breakthroughs.

“There are millions of people microdosing psychedelics right now,” said Karl Goldfield, a former sales and marketing consultant in San Francisco who informally counsels friends and colleagues across the tech world on calibrating the right small dose for maximum mindfulness. It is “the fastest path to opening your mind up and clearly seeing for yourself what’s going on,” said Goldfield.

Goldfield doesn’t have a medical degree and said he learned to dose through experience. He said the number of questions he gets about how to microdose has grown dramatically in recent months.

The account of Musk’s drug use comes from people who witnessed him use ketamine and others with direct knowledge of his use. Details about Brin’s drug use and the Founders Fund parties come from people familiar with them.