(D.C. Office of Planning)

Such as why she was kept on by Mayor Vincent C. Gray (D) when fellow urbanist zealot Gabe Klein got the boot:

As D.C. Council Chairman during the Fenty years, Gray’s planning hearings turned into long conversations about the future of the city. “He and Harriet had built a relationship,” says Klein, by way of explanation for his ouster. “I hadn’t, really.”

Why working in the District is attractive to her:

Though her record would have ensured that plenty of other job offers came her way, she said yes. And why not? It’s easier to get things done in a place with state-like powers and only 13 legislators. “We are the fly-by-our-pants city of doom,” she says, wryly.

Her tensions with Victor Hoskins, Gray’s deputy mayor for planning and economic development and Tregoning’s nominal boss:

At one point, Tregoning was informed that redevelopment of St. Elizabeths Hospital’s east campus would be taken out of her portfolio. “What happened to letting Planning do planning?” she wrote to Hoskins. “My staff is very upset and demoralized by this ... .”

[...]

The biggest clash, however, came over historic preservation. “I am beginning to become gravely concerned by the zealous nature of the historic preservation decisions that I see moving forward in the city right now,” Hoskins wrote last October, offering the campus of St. Elizabeths as an example. He suggested it might be necessary to take the Historic Preservation Office out of Tregoning’s agency—she strongly disagreed, and won.

How she picks her spots:

She’d watched as the last planning director, Ellen McCarthy, battled an aggressive, determined band of NIMBYs who killed a plan for more intensive development in upper Northwest. ...
After green-friendly Mary Cheh was elected councilmember in 2006, the smart growth advocacy group Ward3Vision begged Tregoning to try again with a plan that would make it easier to bring in more residents and better retail. She declined.

[...]

In explaining her reasons, Tregoning is frank. “My predecessor lost her job over the Wisconsin Avenue plan, and I wasn’t convinced that there was a constituency for change,” Tregoning says, her voice lilting up in a characteristic questioning tone. “I wanted them to feel a little neglected.”

And her reaction to the D.C. Council’s decision to grant a tax break for a single-use, low-density CVS to a prime spot near the Georgia Avenue-Petworth Metro station:

“‘What are we, Buffalo?’” one former administration official remembers her grumbling.