For most of the two-hour flight from Geneva to Dublin — as soon as the seatbelt light blinks out — Mark Dybul does not sit. He stands in the aisle, flush against his own armrest, thumbing at his smartphone, while flight attendants and passengers squeeze past. He’s wearing a crisp gray suit, white shirt, and white pocket square. His side swept blonde bangs are thinning but cut across a youthful face. A multicolored United Nations pin clings to his lapel.

“I have to stand when I can,” Dybul says, somewhere in the air between his adopted home in Switzerland and the Irish capital where he’s putting in some face time.

“I have a bad back,” he says — and then, smiling at the irony, “Flying too much.”

Over the course of roughly 24 hours I spent with the former executive director of the Global Fund to Fight AIDS, Tuberculosis, and Malaria, Dybul rarely sat down, even when it meant he was the only one standing. At the Royal College of Surgeons in Ireland, where he was invited to speak about universal health care, Dybul stood, listening from a few paces behind his fellow seated panelists. When a reporter from the Irish Times called to interview him about Ireland’s contribution to fighting infectious disease, Dybul stood with his back against the wall of his hotel room and talked about how the island nation “punches above its weight” by contributing to a multilateral organization.

To operate a global fund, it turns out, requires a global person. For four years Dybul has shuttled between the world’s richest and poorest capitals, rarely spending more than 24 hours in any one place. The repetitive stress of honing his message to donors, matching tight resources to program data in implementing countries — he hates the word “beneficiaries” — and then returning to Switzerland has not beaten him down into his seat, but out of it. It is as though Dybul, like a modern-day Greek hero, has taken on a quest so elemental — ending three global plagues — that the gods demanded a sacrifice: his basic human enjoyment of comfortably sitting down.

For two decades, Dybul has been at the center of a seismic shift in the way global health programs are designed and paid for. A paternalistic donor-recipient model is giving way — slowly and stubbornly — to a constellation of partnerships with strong health systems, not the delivery of treatments by rich countries to poor ones, as their raison d’être. Dybul has pushed for that change and honed a pitch that describes what the future of ending epidemics could look like — and why governments, philanthropists, and even Irish taxpayers should want to be part of it. He wants the world to seize this moment of opportunity. He still has faith in the better angels of our nature.

After four years as the Global Fund’s executive director — during which time he helmed two multi-billion dollar fundraising efforts and helped restore the embattled Swiss organization’s reputation as a global health leader — Dybul stepped down last month at the end of his first term. He is returning to Washington, D.C. and to life as a faculty member of the Georgetown University Medical Center, his alma mater.

“Innovation changes everything, and change doesn’t happen when people stick around for too long,” he told me.

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