In the early days of the Biden administration members of the new president’s White House legislative affairs team had a meet-and-greet with Senate Republicans’ chiefs-of-staff. At the head of this Democratic delegation was Louisa Terrell, Biden’s White House director of legislative.

Terrell, speaking to the audience of powerful Republican aides, laid out how she worked. She felt even in these politically polarized times compromise should be pursued. They wouldn’t agree on everything, but there were deals to be had. At the same time Terrell said, according to four sources with knowledge of this meeting, her team had a job to do and planned to do it.

Terrell’s speech illustrated how she is the tip of the spear of the Biden administration’s team as she fulfills one of the most difficult jobs in America’s deeply divided political landscape: Biden’s congressional fixer and legislative sherpa. Terrell is the leader of the team that takes a proposal from the White House and shepherds it through the winding and sometimes narrow halls of Congress so it can get back to the president’s desk to become law. She is the person who aims to get things done and who is in charge of ushering policy proposals through the congressional maze.

During his presidential campaign and, essentially, through the moment he stepped into the Oval Office as president, Joe Biden has argued that big bipartisan deals are worth pursuing and possible even now. Biden, a multi-decade veteran of the Senate, has argued his roots into both parties in Congress run deep and can produce expansive bipartisan deals.

Enter Terrell, a longtime Biden hand and former chief of staff to senators whose resume also includes stints at some of the most establishment corners of the modern American economy – McKinsey & Company, Yahoo, and Facebook among others. She may not have much of a public profile outside Washington’s corridors of power, but inside Terrell is a vital player. She has been in the room at the most pivotal moments of the major legislative initiatives during the Biden administration.

Terrell’s ties to Biden run deep, all the way back to her youth in Delaware. She did a stint as the executive director of the Biden Foundation and served as a senior adviser and director of congressional engagement for Biden’s presidential transition fund. She is a graduate of Tufts University and Boston College’s law school.

Terrell is famous around Washington DC for her effectiveness and agreeability – among Republicans and Democrats – even as she has climbed to the highest ranks of congressional power. She is one of the small elite group of Biden aides who have been going back and forth between the White House and the halls of Congress, meeting with lawmakers at some of the tensest moments of major negotiations on Covid-19 aid or, more recently, infrastructure.

“Her job is shuttle diplomacy and so she works on both sides of the equation,” said Tom Wheeler, who served as the chairman of the federal communications commission when Terrell was there.

Terrell, in a rare interview with the Guardian, was realistic about finding compromise and bipartisan deals. The infrastructure bill passed but that’s more an example of the exception that proves the rule. Congress has been paralyzed by rank partisanship for years. It’s more normal for even the most seemingly commonsense policy proposals to get stuck in the morass of Capitol Hill legislating.

“You gotta be realistic. There are places where there are synergies and there are places where we’re just going to agree to disagree, so let’s just look around in the backyard and see if there are some things that we can work on,” Terrell said. “And if we can’t let’s just keep staying in touch and make sure you’re getting what you need from the agencies as you do your work. There are lots of ways of engaging even if you’re not trying to dig through a really hard policy issue.”

Senators and staffers, both Republican and Democratic, are quick to note that the Biden administration’s outreach to the Hill is noticeably different than the last two administrations.

It’s not that everyone gets what they want but lawmakers and their aides say they feel more in touch with this White House. That’s in contrast to the last two administrations. The Donald Trump administration is viewed as textbook disorganized and incapable of even the most basic congressional outreach.

“I don’t think I ever knew what was from the Trump White House,” quipped Senator Mark Warner of Virginia of that administration’s legislative affairs team.

But Democrats also say, at times, they found the Barack Obama administration’s outreach lacking.

“People felt like [Obama] didn’t respect the Senate, like he also looked down on senators and the process here and didn’t do the work that, frankly, Louisa is extraordinary at, which is centering senators in what’s going on and listening to them and making them feel heard,” said another Democratic senator granted anonymity to speak candidly about the last Democratic administration.

By comparison, staffers and lawmakers note that they frequently hear from this current legislative affairs team and feel the lines of communication are open.

If there’s any hallmark about the Biden administration’s interactions with Congress it’s the desire to at least make sure members of both parties and different wings within the Democratic and Republican party feel heard. Terrell described how her team doesn’t just approach the Hill as grouped into just Republicans and Democrats.

“I think it’s different and we think about it in a much more segmented place about both progressives, think about our moderates, think about the different segments on the House side – so just a different kind of environment, think about Democrats on certain committees, that whole kind of ethos,” Terrell said. “We, when we’re all talking together about what our approach is, we try to be kind of really personal and as specific as we can. And I think the same thing for Republicans. They don’t just all bunch together.”

She also factors in another column: when lawmakers have been in office for a long time.

Coming in and out of meetings with lawmakers, she is occasionally spotted on the Hill alongside Steve Ricchetti, counselor to the president, and Brian Deese, national economic council director. The trio are some of the closest, highest paid, and most influential aides to Biden.

“It’s a well functioning team and Louisa’s kind of the glue to that,” Warner said.

There are of course Republican aides and lawmakers who remain skeptical or wary of working with the Biden administration’s team, but there are others who speak respectfully of them. Some chiefs of staff rolled their eyes at the introductory meeting with Terrell and her team. But for others it was a successful olive branch.

“I found her to be extremely professional. She was solicitous in terms of looking for feedback. I found her to be straightforward,” said Republican Joe Hack, who until recently was chief of staff to Senator Deb Fischer of Nebraska. “She took the time to meet with my boss to learn about her priorities which I appreciated. And during that conversation I think, again, she was candid about the types of things we might be able to work together on. But she seemed to be a very active, good listener. And I would say my boss who had no opinion of her when she came in, thought highly of her when she left.”

Terrell is the head of a roughly 15-person team charged with helping plow a congressional path for the White House’s legislative agenda.

The job requires her to be part White House liaison, part fixer, and part hostage negotiator. Louisa’s team has held well over 500 phone calls and meetings with lawmakers and their top aides for the Biden administration’s infrastructure deal alone, according to the Associated Press. The team is made of longtime Hill veterans and policy experts. Members of the team are assigned to different members and committees and policy areas.

“Really their job is to be in almost ebb-and-flow contact with all their committees all the time,” Terrell said. “It’s kind of like picking up or checking in all the time and thinking about what their priorities are for that member.”

Like with so many jobs in any presidential administration, the secret effectiveness of Terrell’s role depends on proximity to the president.

Sarah Bianchi, a fellow former official in the Obama White House who is now Biden’s nominee for deputy trade representative, said Terrell maintains credibility on the Hill because “when she speaks they know that’s someone who has a lot of credibility with him. It makes a big difference, particularly in that role.”

“Louisa and the president have something in common,” said senator Cory Booker of New Jersey, who Terrell served as chief of staff for early on as a senator. “They’re both creatures of the Senate and have spent a lot of time here and having reverence for this institution, which I’ll tell you right now goes a long way with senators on both sides of the aisle.”

Asked what she would mark as a win for her team, Terrell pointed to the American Rescue Package, the Biden administration’s Covid relief bill.

“Look, the big victory was – getting the Rescue Package done was just huge,” Terrell said.

In college Terrell rowed and played on the squash team. She also played tennis. For decades her life included serious yoga, but that’s gotten harder in her current job. She is effusively friendly but also retains an athlete’s drive for competition.

“I think healthy competition is – it’s good,” Terrell said.