But their marriage won’t bring their peripatetic ways to an end: Ms. Stebich is some 2,400 miles west of Manhattan — and Ms. Radice and her home and job.

“I’m going to be spending a lot of time on Alaska Airlines,” Ms. Stebich said. “And Anne is a JetBlue fan.”

Such peregrinations aren’t completely new for the couple — both travel extensively for work — or their relationship, which evolved in a series of small steps from far away, even as friends wondered why they hadn’t found each other sooner. Both are successful; both are borderline workaholics; and both are intensely devoted to the arts, and the enjoyment of them. But despite years overlapping at conferences and museum meetings, the two were nothing more than acquaintances.

They had known each other as museum-world colleagues for more than a decade, and Ms. Stebich, 50, said that she had long admired Ms. Radice. And indeed, at 68, Ms. Radice had a long and esteemed career in New York City and Washington, D.C., where she has been an acting chairwoman of the National Endowment for the Arts and was the first director of the National Museum of Women in the Arts.

“I’d always respected Anne from afar, and from afar means I’m sitting in the audience, and Anne is speaking,” said Ms. Stebich, who got the top job in Tacoma in 2005, after stints at the Guggenheim Museum, the Brooklyn Museum and the Cleveland Museum of Art, adding that she had “made no noticeable impression on her in our past professional encounters, to my chagrin.”

Ms. Stebich said that when she did her very best to go up and speak to her, she didn’t really get a lot of attention. That only served to make the prospect of becoming friendly with Ms. Radice “a little more intriguing,” Ms. Stebich said.