Life in city public housing can have its share of challenges. But in Harlem one woman is trying to improve conditions for the residents of the 40 buildings that make up the Fred Samuel Apartments. Our Michael Scotto has the story in the second part our series 'One City, Many Mayors'

Whenever Diana Blackwell walks through Harlem, she's bound to run into someone she knows.

Blackwell is the president of the resident association at the Frederick E. Samuel Apartments, 40 New York City Housing Authority buildings scattered through Harlem.

The 65-year-old took over as president in 2009, just as she thought she'd be trading in the daily grind as an events planner for something more relaxing.

"Retirement was supposed to be rest time," Blackwell said. "Cruises. Plane trips."

Instead, Blackwell finds herself racing through the streets of Harlem, checking in on buildings, working at the vegetable garden she started and tracking the progress of youth programs in NYCHA community centers.

Most days, Blackwell says, she works from 9 a.m. until 11 p.m. She is not paid a dime. It's all volunteer.

"If you see a need, and you have the capability of meeting the need, you do it," Blackwell said. "That's why I'm single."

One need she's identified: improving the conditions of the buildings.

As an 18-year resident of NYCHA, she knows management well, and uses her connections to expedite repairs and help residents navigate bureaucracy.

But Blackwell sees her role as something larger. She wants to build partnerships to improve not just her neighbors' buildings but the community as a whole. 

Those partnerships include programs to help young people get jobs and ensure people have access to greenspace and healthier foods.

Her other big mission: working with the NYPD to improve the trust between cops and the community.

"We get to know them one-on-one," Blackwell said. "They're no longer our men in blue. They're our family and friends."

That work would prime anyone for public office. But Blackwell insists she has no interest to run in an election.

"Never," she said.

Instead, she says, she's satisfied trying to make a big difference in the neighborhood she calls home.