34 Leaders Who Are Changing Health Care

From bold investors to company builders, from research scientists to patient advocates, here are nearly three dozen women and men who are driving progress in medicine and the business of keeping us healthy.

Related: Prepare for the Digital Health Revolution

Joe Biden

Joe Biden.

Former Vice President, Leader of the White House Cancer Moonshot

The 47th Vice President of the U.S. has always been one to roll up his sleeves and get to work. The nation saw that with his tireless effort to boost progress against cancer by changing the culture of research. And he’s still at it.

Related: Vice President Joe Biden Is Coming to Brainstorm Health

Bill and Melinda Gates/Sue Desmond-Hellmann

Bill and Melinda Gates, and Sue Desmond-Hellmann (center).

Cochairs/CEO, Bill & Melinda Gates Foundation

For years, this global health triumvirate has tackled—and edged closer to eradicating—the world’s most intractable (and yet long-neglected) diseases, from polio to malaria.

Atul Gawande

Atul Gawande.

Surgeon, Writer

The celebrated New Yorker writer, who also happens to be a surgeon, has eloquently exposed many of the flaws of American health care—and offered some smart ways to address them, too.

Click here to subscribe to Brainstorm Health Daily, our brand new newsletter about health innovations.

Nora Volkow

Nora Volkow.

Director, National Institute on Drug Abuse

As the nation grapples with an epidemic of substance abuse, Volkow’s groundbreaking work, showing that addiction is a disease of the brain rather than a moral failing, is especially important.

Jonathan Bush

Jonathan Bush.

CEO, Athenahealth

Few are more persuasive—and outspoken—about the need to repair our health care system. The fixes, says Bush: advanced technology, better care coordination, and data-based prevention.

Sean Duffy

Sean Duffy.

CEO, Omada Health

The Google alum’s startup aims to prevent diabetes in people on the cusp of developing it by using a digital scale, a smartphone app, and an online support community.

Arianna Huffington

Arianna Huffington.

CEO, Thrive Global

The queen of new media has brought “wellness” onto the health agenda as never before—a welcome development for the sleep-deprived masses.

Related: Arianna Huffington's Thrive Global: Turning Sleep Into Productivity

Rebecca Onie

Rebecca Onie.

CEO, Health Leads

Onie is pushing for a more expansive medical system; her organization, Health Leads, asks what patients need to be healthy—food, electricity, safe housing—and makes it happen.

Sean Parker

Sean Parker.

President, Parker Institute for Cancer Immunotherapy

His revolutionary institute is a model for academic collaboration, data sharing, and the challenges of managing IP in science. And it’s also taking some of the boldest bets yet in cancer research.

Kathy Giusti

Kathy Giusti.

Founder, Multiple Myeloma ­Research Foundation

Giusti created what is without question the most successful patient advocacy model on the planet—one that, importantly, gets patients, researchers, and industry to sit at the same table.

Peter Hotez

Peter Hotez.

Dean, National School of Tropical Medicine at Baylor ­College of Medicine

A self-described “scientist, researcher, advocate,” Hotez, who focuses on deadly infectious diseases around the world, was one of the first to sound the alarm on Zika in the U.S.

Ngozi Okonjo-Iweala/Seth Berkley

Ngozi Okonjo-Iweala and Seth Berkley.

Board Chair/CEO, GAVI

Former Nigerian Finance Minister Okonjo-Iweala and GAVI CEO Berkley oversee a public health alliance that has boosted access to vaccines in 73 of the world’s poorest countries, tackling scourges like cholera and cervical cancer.

Michael T. Osterholm

Michael T. Osterholm.

Director, Center for Infectious ­Disease Research and Policy, University of Minnesota

When it comes to emerging disease threats, Osterholm has long been the world’s sentinel—and a persuasive exponent of the need to do more to prevent the next global pandemic.

Raj Panjabi

Raj Panjabi.

CEO, Last Mile Health

The Liberian-born physician returned to his native country after its brutal civil war only to face a bigger threat: Ebola. His work to contain that disease—and train local residents to serve as community health care workers—may have saved thousands.

Greg Simon

Greg Simon.

Director, Biden Cancer Initiative

The man who ran the impressive ground game for the White House Cancer Moonshot is a behind-the-scenes visionary who makes progress happen.

Jim Allison

Jim Allison.

Chair, Department of Immunology, the University of Texas MD Anderson Cancer Center

His pioneering, decades-long work in immunology—which led to the discovery of immune checkpoint inhibitors—has changed the way we fight cancer and offered hope to millions.

Jennifer Doudna/Emmanuelle Charpentier

Jennifer Doudna (right) and Emmanuelle Charpentier.

UC Berkeley/Max Planck Institute

They borrowed a bacterial defense mechanism called Crispr and transformed it into a tool that may one day “edit” many diseases right out of our genomes.

Geraldine Hamilton

Geraldine Hamilton.

President and Chief Scientific Officer, Emulate

Emulate’s “organs on chips” technology could revolutionize how food and drugs are tested for safety.

Laura Niklason

Laura Niklason.

Founder, Humacyte

Her efforts to engineer vascular and lung tissue have put her in the vanguard of regenerative medicine.

Michael Gilman

Michael Gilman.

CEO, Arrakis Therapeutics

The former Biogen executive and serial entrepreneur has chased some of biotech’s most interesting experimental spaces. His latest quest? Creating medicines that target RNA.

Katherine Kuzmeskas

Katherine Kuzmeskas.

CEO, SimplyVital Health

Kuzmeskas’s mission is to harness blockchain, the digital ledger technology at the heart of Bitcoin, to combat inefficiencies in ­medical record-keeping and payment systems.

Vivek Ramaswamy

32-year-old Vivek Ramaswamy's company has a new take on drug development.

CEO, Roivant Sciences

The 31-year-old wunderkind and former hedge funder has pulled off some of biotech’s biggest IPOs in recent years. His companies are working to treat everything from Alzheimer’s to cancer.

Bryan Roberts

Venrock partner Bryan Roberts.

Partner, Venrock

A natural communicator and a buoyant supporter of digital health innovation, Roberts also has a hot hand when it comes to investing. He has backed one winner after another.

Anne Wojcicki

23andMe CEO Anne Wojcicki is one of the revolutionary leaders on our list.

CEO, 23andMe

With the recent nod of the FDA, Wojcicki’s battle-tested startup is now the only company in the U.S. that can sell genetic tests and health-risk reports directly to consumers, no prescription necessary.

Related: DNA Test Firm 23andMe Can Now Tell You Your Alzheimer’s Risk Without a Prescription

Mark Bertolini

Mark Bertolini.

CEO, Aetna

The forward-looking and outspoken insurance CEO is focused on population wellness; his employees are rewarded for getting a good night’s sleep and other healthy behaviors.

Joe Jimenez

Novartis CEO Joe Jimenez

CEO, Novartis

Jimenez has championed the need to build health care infrastructure in the developing world—and to use ready-made tech when possible. One example: using SMS messaging via mobile phones to ensure essential medicines like vaccines are where they’re needed.

Sandi Peterson

Sandi Peterson.

Group Worldwide Chair, Johnson & Johnson

J&J’s first-ever group worldwide chairman is leading the charge to transform the $72 billion, 131-year-old giant into a cutting-edge health technology company.

Sue Siegel

Sue Siegel.

CEO, GE Ventures and Healthymagination

CEO Jeff Immelt lured the well-respected Silicon Valley VC to GE in 2012; she now leads innovation and growth initiatives at the 125-year-old company, partnering with its $18 billion med-tech division.

Bernard Tyson

Bernard Tyson.

CEO, Kaiser Permanente

Tyson leads one of the few organizations in America that seem to get health care right; nonprofit Kaiser—a health plan, hospital system and physicians group all in one—offers high-quality, (relatively) affordable care.

A version of this article appears in the May 1, 2017 issue of Fortune as part of the "Future of Health" package. See the rest of the package here.

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