One of the first things that Capricia Penavic Marshall did upon being appointed by Barack Obama to serve as the chief of protocol was to call those who had held the post before her. The glamour that came with the role’s ceremonial duties, typically documented in state-dinner photographs, was all too familiar to Marshall, who previously served as the White House social secretary. What she didn’t know was what it took to achieve lasting success in her new role.

Several of those that Marshall called spoke of successes that had outlasted their term, such as the Experience America series that took foreign envoys to far-flung corners of the country such as Wyoming and Alaska. But Marshall’s predecessors also lamented the initiatives that disappeared when a new president or secretary of state came to power.

Marshall realised that in addition to managing the very public daily operations of the office she would need a laser focus on long-term strategy if she hoped to establish any durable accomplishments. Over her first year, Marshall met with budget specialists and operations experts to establish how to enmesh initiatives so deep into the bureaucratic fabric that future administrations would not be able to sweep them away.

Almost four years later, as Obama finishes his first term and Marshall’s patron, Hillary Clinton, prepares to leave the department, the protocol chief points to an administrative trophy: a new five-person Diplomatic Partnerships Division with its own line in the federal budget. That – perhaps more than anything, Marshall believes – will determine her legacy, even if she is forced to vacate the office after November’s elections.

“Management in government is so different from management in the private sector,” reflects Marshall, 47. “You have a very finite time in which to engage and actually make things happen.”

Marshall had long known the protocol office as the people in her own government who were always looking out for others’ interests. Marshall had been one of Hillary Clinton’s confidantes since Bill’s 1992 campaign and in his second term was rewarded with the biggest plum the first lady has to offer: the job of White House social secretary. For four years, Marshall would plot ceremonial occasions with the best interests of the Clintons in mind, while a State Department official would negotiate on behalf of the visiting dignitary being honoured. “As the social secretary, the fine-tuning of the event logistics are what we’d look at – how things are flowing for the president and first lady – because you are creating their style,” she reflects. “From the chief of protocol perspective, you’re really looking at the invitee.”

Indeed, from her new station down Pennsylvania Avenue, Marshall has learned the extent to which the protocol office serves as a concierge desk to foreign diplomats in Washington. Marshall oversees an office of 79 employees, two-thirds of whom are either civil servants or career diplomats rotating in for a posting of two or three years. When hiring political appointees to fill the remaining slots, Marshall often asks how they would approach a problem, resisting those who are ready with a confident answer. Instead, she’s drawn to those who talk about the questions they would ask. “You have to have an ability to listen, to pause,” Marshall says, “and be able to still move forward our agenda in a very gentle but strong direction.”

When a foreign head of state is headed to town, Marshall turns her office into a modest intelligence-gathering operation. Staff members visit the country’s embassy in Washington and contact American diplomats posted abroad to assemble a dossier on the official’s interests and preferences. Marshall convenes a core team meeting in her office to review what they’ve learned and then pass on their event-planning recommendations to the White House social office and National Security Council.

But it is with the permanent ambassadorial corps – more envoys are posted in Washington than in any other capital – that Marshall develops the closest relationships. She meets many of them when they arrive and chaperones new ones to the Oval Office to present their credentials to Obama. “We are their agents,” says Marshall, who has an ambassadorial title but is proud to be on a first-name basis with her peers. “We make sure all of their needs are taken care of.” Marshall has helped diplomats place their children in local schools; she found a place for one envoy to stay for two days when his official residence suffered a water leak. One problem she has yet to solve: how to stop the desperate calls from airports where ambassador feel they are being hassled by overzealous security screeners. It is in cases like these that Marshall tells her staff to disregard the well-documented office chain of command.

“I want to delegate to them, but when it’s something very personal to an ambassador I’m very hands-on,” she says. “Everyone in the office knows if there’s an issue that arises I have to be first in line to know. They have to send it right to me, no matter what time.”