There are no “poor doors” in the new Regent Park. Instead of apartment building entryways segregated by income level, the subsidized townhouses resemble the market-rate homes across the street, erasing the stigma of poverty. A recreation center has opened down the block from a new arts building, both of them free to use.

“We want to make sure people aren’t isolated and their mental health is strong,” said Pam McConnell, a deputy mayor of Toronto who lives in the neighborhood. “You do that by offering activities that bring them out of apartments, so everyone feels like they belong.”

Ms. McConnell said the city has mandated that new businesses in Regent Park — among them a bank, a cafe and a supermarket — employ residents, providing nearly 1,000 jobs, a boon in a neighborhood where around 70 percent of the population lives in poverty, according to the last census in 2011, which listed 10,000 residents.

But mixing incomes goes only so far without incorporating other community needs, Ms. McConnell said.

“You have to make sure the people here who were disempowered gain their power and have their voice always acknowledged,” she said.

Grass-roots participation lies at the heart of Regent Park’s billion-dollar transformation. From the start, the city and the developer incorporated residents’ needs into the design, from ensuring they were not forced out of the neighborhood, to stocking food that met Muslim religious requirements, and scheduling private swimming and yoga classes for women.