She’s Virginia Savage McAlester, her family’s lived in the same Swiss Avenue home since 1921, her mother rescued other homes on Swiss and the daughter is now the author of what the NYTimes calls the ‘magisterial’ A Field Guide to American Houses. But you knew all that, surely, because McAlester is the founder and past president of Preservation Dallas.

The new volume is actually an expanded updating of McAlester’s 1984 book of the same name — because that volume ended with homes built in 1940, and it so happens, some “80 percent of American homes have been built since then.” So the new edition is a big deal. Yet the 70-year-old McAlester managed to complete it while recovering from leukemia. (Entertainment Weekly gave it an A and called it the “photo-packed bible” of American home design.)

When she started her work as a preservationist in the 1960s, development-crazy Dallas, needless to say, was not a welcoming city. But neither was Texas or even America in general.

The local Lakewood Bank would not lend against [Swiss-Munger] properties (and her father had been chairman of the board). They were, apparently, worthless, she said: “I guess one of the reasons that I wrote the first book is we needed to have a survey.”

She would go on to establish a fund that expanded on her mother’s isolated interventions, buying and improving 27 houses on an adjacent street, Munger Place. “It was the first place in the country Fannie Mae had loaned on old houses in the inner city,” she said.

Peter Brink was working to save the 19th-century cast-iron commercial buildings in Galveston when he met Ms. McAlester. He later became the senior vice president for programs at the National Trust for Historic Preservation. But at the time, he was a lawyer without any useful architectural training.

“A lot of preservationists in these early decades reacted intuitively,” Mr. Brink said. “I could see these magnificent structures. I don’t know what style it is, but I don’t think it should be torn down.”

“A Field Guide” became a briefing book for making that case. “I use it, and I think many others do,” he said. “I’ve never seen anything that comes close to what it does.”