Harlem community advocate Nina DeMartini-Day has spent the bulk of her life fighting to improve the lives of the poor and underprivileged in the neighborhood despite critics who argue her reforms ultimately hurt those she seeks to help.

For decades, her work in city government and housing development for DDM Development, a company she helped found, has revitalized dilapidated buildings and homes in Harlem, raising the standard, but also the cost, of living for its residents, a two-edged sword that has led to gentrification.

Today Harlem’s real estate market has been overhauled with new development, raising rent prices and forcing many life-long Harlemites out of their homes.

“I do see what’s happening,” DeMartini-Day admitted during a recent interview. “It’s that issue of once it becomes a little safer, is that a bad thing for the residents who live here? I don’t think it is. But does it mean other people might come in? Yes.”

Now 69, DeMartini-Day serves as a board member on the New Harlem East Merchant Association (NHEMA), a regional coalition of small business advocates that works on initiatives and community reforms like hiring homeless individuals to pick up trash around the area and occasionally closing streets to organize morale-boosting block parties for local residents.

NHEMA’s most-recent endeavor was to open a community plaza at Harlem’s 125th St. Metro North underpass, where local food growers host seasonal farmers markets. The new gathering place exists in the same area locals characterize as a haven for the homeless, where people perceived to be homeless often gather, panhandle, and sleep on surrounding streets with shopping carts and luggage filled with their worldly possessions.

Some advocacy groups argue NHEMA is gentrifying the neighborhood.

“They are systematically, methodically doing this to the community,” says Jason Grimes, member of the homeless advocacy group Picture the Homeless, which is fighting to change city policy on how homeless individuals are perceived and treated by police and aid groups. “A lot of the small businesses have been displaced by the large conglomerates,” he added.

DeMartini-Day argues that claim runs counter to her entire career. A devout Catholic from the Philadelphia metro area, she began working with the poor and needy after moving to New York in 1974, serving in several non-profit organizations and earning a business degree before joining the Koch administration a few years later as first assistant commissioner in the real estate development division.

In July of 1987, DeMartini-Day resigned from the Mayor’s office amid controversy when her boss, Terrence Moan, was involved in the purchase, resale, and sales negotiations of several Manhattan apartments owned by DeMartini-Day’s unincorporated business DDM Development. Neither DeMartini-Day nor Moan was charged with a crime.

After quitting her job, she started working with Catholic parishes in East Harlem, which at the time, amid the height of the crack epidemic of the late 1980s and early ‘90s, suffered from tremendous urban blight.

“There were a lot of empty buildings and lots,” she recalled. “There were parish priests who thought there must be a way to build affordable housing.”

DeMartini-Day and Moan worked with late parishioner Robert Lott, who served as pastor of St. Francis De Sales, to found what is now known as the Lott Community Development Corporation. Together, their organizations have created more than 1,000 affordable housing units for low-income families.

They also created what is now known as the Thurgood Marshall Academy for Learning and Social Change on 135th Street in Harlem.

But improving the neighborhood encouraged outsiders to move into Harlem. Increased demand for housing raised rent prices and increased the cost of living. DeMartini-Day argues that effect is inevitable.

“We have never built luxury housing or condominiums,” DeMartini-Day said of her career. “We have seen market rate housing come in. It’s very hard to totally condemn the development for new buildings because it also brings diversity and a voice. “

NHEMA is a community organization that has no governmental authority, but it was formed amid Harlem’s ongoing demographic shift. It may be a product of that shift, but DeMartini-Day says it is not the cause.

As the lone white woman on a board that serves the economic interests of a predominately black neighborhood, DeMartini-Day admits she sometimes feels her intentions are questioned because of her race.

“What people might say about me they probably don’t say to me,” she said.