Dr. Mary Bassett has a big job, looking out for the health of all New Yorkers in all of New York's neighborhoods. It is the culmination of a lifetime spent pursuing equality — through medicine.

"Poor health outcomes tend to cluster in neighborhoods that people of color call home and where many of the residents live in poverty."

Dr. Mary Bassett thought she was going to be a physician who treated patients.

But, during her residency at Harlem Hospital in the early 1980's, she realized that her work needed to extend into the community.

"Seeing what I saw there, the revolving door, the patients we'd admitted and patched up and sent out who were readmitted, I felt the place that needed attention was outside the walls of the hospital and that what we were doing inside the walls of the hospital was never going to be enough," said Dr. Bassett.

Dr. Bassett is entering her fourth year as city Health commissioner.

She was the voice of reassurance during a Legionnaires outbreak in the Bronx two summers ago, and the public face of the city’s response to the Zika and Ebola crises.

Bassett admits her role as the city’s top health official took some adjustment.

Most of her work is about the day-to-day public health challenges of a big, diverse city. For a variety of reasons, people in higher-income households have better health outcomes.

Her attention to this inequality is very much in accord with Mayor de Blasio’s mission to rewrite the “Tale of Two Cities.”

"We have lower flu shot rates among black communities that made it also important to take the message to communities that we most need to reach cause we haven't succeeded in convincing them to get a flu shot," said Dr. Bassett.

"You need to get these things into the community conversation," said Dr. Bassett. "That's why as health commissioner I need to go out there too. So it really is based on my beliefs, but I hope the optics are good."

She is implementing a program called Thrive NYC.

"Now imagine a city where the path to taking care of your mental health is crystal clear," she said.

The program addresses the lack of mental illness services in poorer communities and the Community Health Profiles program examines neighborhoods for the root causes of health problems in them.

"It's clear that long-standing and rising income inequality, the history of racial residential segregation, has led to startling health inequities across the neighborhoods of this city," said Dr. Bassett.

Two years ago, Bassett appeared in one of her department’s anti-smoking ads, continuing work she began as a deputy health commissioner under Mayor Michael Bloomberg.

"Nicotine is very addictive, but you can quit," said Bassett. "I quit. My body felt better and I was no longer burdened with addiction."

Mary Bassett grew up in Washington Heights, the daughter of a white mother and a black father. They were activists who imbued her with a "sense of duty."

"Because my mother was white she would often negotiate the rental and then we would all move in and there would be an uproar that a black family had moved into the building," said Bassett.

A street in her old neighborhood is named for her late father, a microbiologist with a PHD who grew up in segregated rural Virginia. Bassett remembers visits to her dad’s family when she was a little girl. Back then, her parents’ interracial marriage was illegal in the state of Virginia.

"Being told that if I got lost somehow that I should tell them that one of my father's sisters was my mother," Bassett said. "That I shouldn't identify my mother as my mother."

"I knew I could get my family into trouble just by pointing out who my mother was," she said.

"Certainly growing up in a family that was committed to civil rights, was a mixed race family both with social sanctions and legal threats had an effect on my alertness to the issues of race," said Bassett.

At 17, Bassett helped organize a takeover of the administration building at the Fieldston School in Riverdale, protesting the lack of Black and Latino students, and was quoted in the New York Times, "We don't want any more nice chats with the administration... we've had plenty of those."

As a college student, she worked at the Black Panther Party free health clinic in Boston giving sickle cell anemia screenings.

Her sensitivity to issues of income, race and health came more sharply into focus as the sole black woman in her graduating class at Columbia Medical School, where she went to work at the School's affiliate hospital, Harlem Hospital.

"Everybody thought that everything that was done at Harlem Hospital in those days was second rate and terrible and that the patients were second rate and responsible for their illnesses was a common thing you heard from people," said Bassett.

"Some of its tone, some of its respect," she said. "Recognizing that people when they are poor and their choices are much more limited than they should be, that they are committed to their dignity and respect. They don't want to be treated as though they are stupid."

After medical school, Bassett spent 17 years in Zimbabwe, fighting AIDS and infant mortality, and promoting immunizations. For a single mom with two young daughters it was not an easy commitment.

"There was no doubt that the whole project was really succeeding in improving the health of the population," said Bassett. "It's really where I learned the power of public health."

The idea of public health as a social justice issue is more relevant than ever.

President Trump and a Republican congress are promising to overhaul health care policy.

Critics fear a disadvantage for poorer communities.

"For a doctor to put her head down now just do our job see it narrowly as coming to work and just seeing our patients when our patients are threatened by losing access to health care and other safety net programs flies in the face of the oath that we all have taken," said Bassett.

"Nobody who works in public health for a long time continues to think of it as a purely technical enterprise," said Bassett. "We got to get technical stuff right.  But principally whether people live a long or short life is determined by the level of justice in our society."

Another new Department of Health project is called "neighborhood health action centers."

These centers will combine clinical and social services in medically underserved communities. They are scheduled to begin opening later this year.