By Lauren Herstik | The New York Times

Los Angeles conjures a particular image in the popular imagination: sprawling and spacious, dotted with single-family homes and riddled with traffic. But Angelenos have signaled that they are ready for a change, most recently by voting down a measure that would have slowed new construction for two years.

The effort to slow construction, known as Measure S or the Neighborhood Integrity Initiative, was financed mainly by Michael Weinstein, the president of the Hollywood-based AIDS Health Foundation. Mr. Weinstein’s office is on the 21st floor of a Hollywood skyscraper with a view of the hills, next to the future site of two 28-story mixed-use residential towers.

Mr. Weinstein said that kind of development was out of character for the neighborhood. He and other supporters of Measure S have contended that new luxury developments can contribute to rising rents.

The Measure S campaign pitted slow-growth factions, who called the city’s planning process corrupt, against a coalition of public officials, developers, labor groups and others who conceded that while reform was necessary, so was growth.

Now that the pro-growth group has prevailed, the question is: How does the city move forward? Can it overhaul the planning process, allow innovation and still please the disparate stakeholders within its 503 square miles?

Measure S, which was defeated last month, was the third in a trio of transformative local ballot measures. In November, Angelenos approved a $1.2 billion bond to build affordable housing, along with a half-cent sales tax increase to pay for mass transit.

Taken together, the votes are “a very clear statement from the voters that they’re interested in a different Los Angeles,” said Christopher Hawthorne, who teaches urban and environmental policy at Occidental University and is the architecture critic for The Los Angeles Times.

The city’s mayor, Eric M. Garcetti, who was swept into a second five-and-a-half-year term last month by 80 percent of the voters, heard the statement. He is empowered by these votes, with billions of dollars at the city’s disposal to address homelessness and improve infrastructure. But the vocal minority who fought to curtail development with Measure S still remains and he cannot ignore them.

“That’s L.A.’s biggest and most exciting challenge: How do you harness the momentum, the investment and even the disruption in a way that still addresses social needs?” Mr. Garcetti said.

Mr. Hawthorne has put forth the notion of a “Third L.A.,” a redefined vision of the city. The “First L.A.” was marked by the arrival of water in the 1880s and the city’s first population and real estate booms; it was a city of great civic ambition, public architecture and great experimental multifamily housing.

But it is the “Second L.A.” that is most enduring: the post-World War Two modernist mecca, a patchwork of single-family homes crossed by freeways and defined by the car. It is the city of Julius Shulman’s iconic photos of glass Case Study Houses overlooking suburban sprawl, and David Hockney’s paintings of backyard swimming pools.

“The dream or ambition embodied by the Second L.A. begins to break down into the ’80s and ’90s,” Mr. Hawthorne said.

The city began to fracture along racial and economic lines, leading to the 1992 Rodney King riots, which decimated much of South Los Angeles and Koreatown.

It is those neighborhoods that are now the focal point of the emerging Third L.A.

Koreatown is well served by mass transit: Three metro stops along Wilshire Boulevard link it to downtown Los Angeles.

“It’s denser and people are choosing to live there because they want to give up some square footage in exchange for more,” Mr. Hawthorne said. That’s more time, access to transit and a pedestrian culture.

Successful development in Koreatown has, in turn, increased interest nearby, said Marqueece Harris-Dawson, councilman for South Los Angeles.

“In a place like South L.A., which investors have systematically avoided, the red lines are just now falling away,” Mr. Harris-Dawson said. “Investors are enthusiastic, bullish, excited about mass transit coming through South L.A., about the opportunities along the main corridor, and excited about the untapped potential.”

Had it passed, the Measure S two-year building moratorium threatened to shut down new opportunity for South Los Angeles and neighborhoods like it. But in simply running the campaign, “S” proponents may have expanded that opportunity, by effectively starting the conversation about how to make Los Angeles’ planning process more transparent and effective.

The mayor signed an executive directive on March 9 establishing a planning task force, banning closed-door communications between planning commissioners and developers, and setting up programs at City Hall to guide development around transit and affordability.

Mr. Garcetti said he planned to eliminate regulations that stymie innovation, “whether it’s the size of units, or the connectivity of transportation modes.”

“We’re writing the rules as we go,” the mayor said, acknowledging “that can be very disruptive to people.” But, he added, “We need to get with it.”

All of this signals a move toward building that Third L.A.

“I see a series of many urban centers along the transportation corridors,” said Nelson Rising, chief executive of Rising Realty Partners, which has worked extensively in downtown Los Angeles.

“Anything near a transit stop will become viable and attractive,” Mr. Rising said. He pointed to specific hubs of density along the purple line, which currently links downtown to Koreatown and is set to extend all the way to Santa Monica with the passage of the transit measure. He also pointed to the Expo Line, which runs parallel to Interstate 10 and connected downtown to Santa Monica in May 2016.

The city planning department has laid the groundwork for these changes. Last year it enacted a mobility plan to diversify transportation modes by 2035, and created a new industrial live-work zone in response to demand from commercial and residential sectors for that kind of multiuse development.

Mr. Hawthorne speculated that the Third L.A. might be a city in which pockets of the First and Second L.A. peek through.

Mayor Garcetti is thinking hard about the look of the city.

“People entrust and elect leaders to take some risks and to be big and bold about the projects we do,” he said.

He said he hoped to turn an eye to the streetscape, to engage Angelenos at street level in a way the city never had to when the car was king.

It is why he has pursued large projects like a stretch of the Los Angeles River planned by the local “starchitect” Frank Gehry, the visually stunning Broad Museum and a forthcoming $1 billion museum by the filmmaker George Lucas. It is also why he is considering bringing in a chief design officer.

Mr. Garcetti said he envisions “a guru who can marshal the forces of the city and look at every bus stop, curb, utility box, every facade, every subway portal: These are moments to inspire and connect.” He added, “We should seize that moment.”