With the town finding one excuse after another to keep out affordable housing, the New Jersey Supreme Court issued a second landmark ruling in 1983. In the decision, known as Mount Laurel II, the justices ordered all New Jersey suburbs to rewrite their zoning laws and allow a “fair share” of affordable housing. But that was hardly the end of it. Not until 1997, after endless planning board hearings, council meetings, and multiple attempts to reach a legislative solution, was the housing development finally approved.

In 1999, construction started on the affordable housing complex. A year later, the first tenants moved into the Ethel R. Lawrence Homes, town houses whose clean, contemporary exteriors and manicured lawns blended in with nearby market-rate developments. Many came from disadvantaged communities like Camden, just 15 miles away, which has the nation’s highest crime rate.

“A ghetto in the field” was how some townspeople envisioned the new housing. “Everyone was scared, apprehensive of the unknown,” recalls Mount Laurel’s former mayor, Peter McCaffrey, who had been booed by his constituents for supporting the venture. No one could predict whether life in and around the Mount Laurel complex would affirm or mock the ideals of faith, hope, tolerance and equality, names given to streets in the complex.

Thirteen years later the answer is at hand, and it is unambiguously positive. “Climbing Mount Laurel” shows that the well-off residents of the town have been unaffected by the new housing. There have been changes in life in Mount Laurel. But the changes are entirely consistent with those in demographically similar suburbs that surround the township. In all these communities, crime rates fell. Property values rose during the housing boom and dipped during the recession. Tax rates declined. Even in the Mount Laurel neighborhoods closest to the affordable housing, property values were unaffected. To most residents, the fact that poor families now live in Mount Laurel has proved entirely irrelevant. Today, many well-to-do Mount Laurel residents don’t even know that affordable housing exists there.

Where you live profoundly shapes who you are. “I would go as far as to argue that what is truly American is not so much the individual but neighborhood inequality,” concludes the Harvard sociologist Robert J. Sampson in his landmark 2012 book, “Great American City.” The families that migrated to Mount Laurel — earning from 10 to 60 percent of median income — obtained more than a nicer house. They secured a new lease on life, a pathway out of poverty for the adults and a solid education for the children.

“CLIMBING Mount Laurel” makes good use of what social scientists call a natural experiment — since there weren’t enough units to accommodate everyone who wanted to live there, the researchers could compare the experiences of the successful and unsuccessful applicants. At the outset the two groups led similar lives, but much has changed since then.

Those who didn’t secure housing report that their neighborhoods remain pockmarked by violence. But the families who came to Mount Laurel have settled into a tranquil world — so quiet, one resident tells me, that for the first year she had to keep the TV on to fall asleep. Deer are a familiar sight, and frogs sometimes land on their doorstep. “I used to be afraid of gunshots,” another tenant says. “Now I’m afraid of skunks.”