Everyone seemed to be focusing more on clothes, nails, hair and the other aspects of the traditional female corporate uniform than they might have on a less consequential day. It didn’t read as shallow; it was just the easiest way to connect with Ms. DuVally, to convey warmth and support.

Andrew Williams, a Goldman spokesman, stuck his head into Ms. DuVally’s office soon after she arrived. “Welcome, Maeve,” he said, smiling. Ms. Krasky sent an email: “I’m so glad to know the big day is finally here.” Another woman hugged Ms. DuVally in the hallway, saying, “Oh, wow, you look gorgeous.”

“I’ve been hugging a lot of people,” Ms. DuVally said. “Before I decided to come out, I don’t think I had ever hugged anyone at work.”

That first day, Ms. DuVally discovered a secret the rest of the women on the 29th floor already knew: The women’s bathroom had a cushioned leather bench. She used the space for the first time, bringing her purse with her to check her makeup.

There were hiccups. The badges Goldman’s security apparatus printed out for her visitors still referred to her as Michael, and at one point, Mr. Williams accidentally used the wrong pronoun. Ms. DuVally said she had prepared herself for little slips like those. She knew some younger transgender people who got angry every time someone misgendered them, she said, but she had decided not to let it bother her too much.

She received gifts, including a makeup bag. The commodities trading team sent flowers, a tightly packed cluster of white orchids. “During this important point in your life, we wanted to let you know how happy we are for you,” a card read. “We are full of genuine admiration and respect for your bravery and choice to be happy.”

On the evening of June 6, Ms. DuVally, in dress slacks and a soft blue blouse, was one of a dozen Goldman Sachs volunteers at the Children’s Museum of Manhattan’s Pride Night. They looked on as 30 or so kids raced around the museum after hours, splashing in its water exhibit and painting a giant pride flag on a canvas spread across the floor.

Like many of the other volunteers, Ms. DuVally did not know exactly what to do. She eventually sat down at a child-sized table arrayed with paper and art supplies. A girl of perhaps 6 sat down across from her, and they both began to draw. The girl wrote her name, “Amelia,” in light blue. Ms. DuVally chose a different color — blue, red, pink, green and crimson — for each of the letters in MAEVE.