Although much less of a public figure than his new boss, O’Neill is quite well-known in the increasingly well-funded and tight-knit longevity community. His acquaintances include the prominent longevity influencer Bryan Johnson, who describes him as “a soft-spoken, thoughtful, methodical guy,” and the billionaire tech entrepreneur Peter Thiel. In speaking with more than 20 people who work in the longevity field and are familiar with O’Neill, it’s clear that they share a genuine optimism about his leadership. And while no one can predict exactly what O’Neill will do, many in the community believe that he could help bring attention and resources to their cause and make it easier for them to experiment with potential anti-aging drugs. This idea is bolstered not just by his personal and professional relationships but also by his past statements and history working at aging-focused organizations—all of which suggest he indeed believes scientists should be working on ways to extend human lifespan beyond its current limits and thinks unproven therapies should be easier to access. He has also supported the libertarian idea of creating new geographic zones, possibly at sea, in which residents can live by their own rules (including, notably, permissive regulatory regimes for new drugs and therapies). “In [the last three administrations] there weren’t really people like that from our field taking these positions of power,” says Livingston, adding that O’Neill’s elevation is “definitely something to be excited about.” Not everyone working in health is as enthusiastic. If O’Neill still holds the views he has espoused over the years, that’s “worrisome,” says Diana Zuckerman, a health policy analyst and president of the National Center for Health Research, a nonprofit think tank in Washington, DC. “There’s nothing worse than getting a bunch of [early-stage unproven therapies] on the market,” she says. Those products might be dangerous and could make people sick while enriching those who develop or sell them. “Getting things on the market quickly means that everybody becomes a guinea pig,” Zuckerman says. “That’s not the way those of us who care about health care think.” The consumer advocacy group Public Citizen puts it far more bluntly, describing O’Neill as “one of Trump’s worst picks” and saying that he is “unfit to be the #2 US health-care leader.” His libertarian views are “antithetical to basic public health,” the organization’s co-president said in a statement. Neither O’Neill nor HHS responded to requests for comment.